Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

Home to the plants of the Sonoran, Chihuahuan and Mojave Deserts

Cirsium ochrocentrum, Yellowspine Thistle

Glossary

The botanical glossary used in Southwest Desert Flora is an alphabetical list of words or terms relevant to the descriptions here. In addition to the more difficult or unusual words defined here the glossary also provides definitions to some of the more common day-to-day botanical words that are not necessarily understood by all readers. This glossary is regularly updated or modified.

Alphabetical Listings
[A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M] [N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] [Y] [Y] [Z]

[A]

Abaxial
The side away from the axis, for instance the lower surface of a flowering plant leaf; compare Adaxial).
Acaulescent
An adjective descriptive of a plant that has no apparent stem, or at least none visible above ground. Examples include some species of Agave, Oxalis and Attalea.
Acerate
Acerose; needle-shaped (long and pointed)
Achene
A small dry indehiscent one seeded fruit.
Actinomorphic
Regular; radially symmetrical; may be bisected into similar halves in at least two planes. Applies e.g. to steles and flowers in which the perianth segments within each whorl are alike in size and shape; compare Regular; contrast with Asymmetrical, Irregular, Zygomorphic.
Aculeate
Armed with prickles; e.g. the stem of a rose.
Acuminate
Tapering gradually to a point.
Acute
Sharply pointed; converging edges making an angle of less than 90°; compare Obtuse.
Adaxial
The side next to the axis; e.g. the upper surface of a flowering plant leaf; compare Abaxial.
Adnate
Grown or fused to an organ of a different kind, especially along a margin; e.g. a stamen fused to a petal; compare Connate and Caudex.
Alkaline soil
Alkaline or alkali, soils are clay soils with high pH (> 8.5), a poor soil structure and a low infiltration capacity. Often having a hard 'pan' or hard calcareous layers from 1½ feet or deeper.
Alluvial fan
A fan or cone-shaped deposit of granular fertile soil deposited by streams or other drainage from mountainous terrain. The formation of one or more alluvial fans into a single fan against a slope is called a bajada (see Bajada).
Alternate
Leaves or flowers borne singly at different levels along a stem includes spiralled parts; or (as preposition) when something occurs between something else, for example stamens alternating with petals; compare Opposite
Androecium
Male parts of flower; the stamens of a flower collectively.
Androgynous
With male and female flowers in the same inflorescence.
Angiosperms
Flowering plants; plants with developing seeds enclosed in an ovary.
Annual
A plant that completes its life cycle and dies within one year.
Anther
Pollen-bearing part of the stamen.
Anthese
1. (of a flower) the period during which pollen is presented and/or the stigma is receptive.
2. (of a flowering plant) the period during which flowers in anthesis are present. note: not defined for some cases, such as when pollen is released in the bud.
Antrorse
Directed towards or upwards, e.g. of hairs on a stem. See also Retrorse.
Pollen-bearing part of the stamen.
Apetalous
Without petals.
Apex
(plural apices) The tip; the point furthest from the point of attachment.
Appendage
A secondary part attached to the main structure; an external growth that seldom has any obvious function.
Appressed
Pressed closely, but not fused; e.g. leaves against a stem.
Arachnoid
Cobwebby, from being covered with fine white hairs.
Arborescent
Tree-like in growth or general appearance.
Areole
(from areola) As with cacti, the area between the veinlets of a leaf or the region of a cactus bearing the flowers and/or spines.
Ascending
Spreading horizontally, then becoming erect.
Asexual
Of reproduction that does not involve the gametes; i.e. vegetative reproduction.
Asymmetrical
Irregular, unequal, lacking any plane of symmetry.
Auricle
(adj. auriculate) usually of leaves; basal appendages shaped like an ear or earlobe.
Awn
Fine bristle-like appendage; e.g. terminating or on the back of glumes and/or lemmas of some grass spikelet’s.
Axil
The upper angle between one part of a plant and another; e.g. the stem and a leaf.

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Bajada
An alluvial fan of deposits of sediment by a stream settling onto flats at the front of a mountain. Derived from the Spanish word bajada; meaning with a sense of “descent” or “inclination” (see Alluvial fan).
Barbellate
(barbellae) With barbed hairs.
Basal
At the base, situated or attached at the base.
Beak
A prominent pointed terminal projection, especially of a carpel or fruit. adj. beaked.
Berry
An indehiscent fruit, with the seeds immersed in the pulp, for instance tomato.
Biennial
Plant which completes its life cycle and dies within the second year; usually also forms a basal rosette of leaves the first year and flowers and fruits the second year.
Bilabiate
Having two lips; e.g. the form of the petals in many irregular flowers.
Bilateral
Arranged on opposite sides; e.g. leaves on a stem.
Bipinnate
Twice pinnate; for example of a compound leaf with individual leaflets pinnately divided.
Bipinnatisect
A pinnatisect leaf with deeply dissected segments.
Bisexual
Plant flowers bearing both male and female reproductive organs; usually, flowers with both stamens and carpels; hermaphrodite. See Perfect.
Blade
The lamina or flattened part of a leaf, excluding the stalk.
Bloom
A fine white or bluish waxy powder occurring on plant parts, usually stems, leaves and fruits. It is easily removed by rubbing.
Bract
Modified leaf associated with flower or inflorescence, differing in shape, size or color from other leaves (and without an axillary bud).
Bramble
1. A prickly shrub of the genus Rubus of the rose family, including the blackberry and the raspberry. 2. A prickly shrub or bush.
Bristle
Straight stiff hair (smooth or with minute teeth).
Bulb
(adj. bulbiferous), thick storage organ, usually underground, consisting of a stem and leaf bases (the inner ones fleshy).
Bur or Burr
Loosely, a prickly fruit; a rough or prickly propagule consisting of a seed or fruit and associated floral parts or bracts.

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Caducous
Falling off early, for example the sepals of poppies, that fall off when the petals begin to open; compare Persistent and Fugacious.
Caespitose
Calcareous
A soil type rich in calcium carbonate (CaCO3). Southwestern calcareous soils contain heavy amounts of limestone and lime. (see Caliche and Limestone.
Caliche
A hardened natural cement of calcium carbonate (CaCO3) that binds other materials—such as gravel, sand, clay, and silt. It is generally light-colored and occurs in arid or semi-arid regions in the Sonoran and Mojave Deserts. The term caliche is Spanish originally from the Latin calx, meaning lime. see Calcareous and Limestone.
Calyculus
(adj. calyculate) (calyculi) (1) a cup-shaped structure formed from bracts, (2) in some Asteraceae, an extra set of bracts or phyllaries just below the involucre simulating a calyx; an involucel.
Calyx
(Plural calyces) the outer whorl of a flower, usually green; the sepals of one flower collectively.
Calyx tube
A tube formed by the fusion of the sepals (calyx), at least at the base.
Campanulate
Bell-shaped.
Canescent
Approaching white in color, covered with dense white (or grayish-white tricomes) down or wool.
Capitulum
A dense cluster of sessile, or almost sessile, flowers or florets; a head.
Capsule
A dry fruit formed from two of more united carpels and dehiscing when ripe (usually by splitting into pieces or opening at summit by teeth or pores).
Carpel
The basic female reproductive organ in flowering plants.
Catkin
A spike, usually pendulous, in which the mostly small flowers are unisexual and without a conspicuous perianth; e.g. willows, poplars, oaks and casuarinas. The individual flowers often have scaly bracts; they are generally wind-pollinated. The catkins are usually shed as a unit.
Caudex (plural: caudices)
Literally the stem of a plant, but also used to mean a rootstock, or particularly a basal stem structure or storage organ from which new growth arises. See also Connate
Caudiciform
Literally meaning "stem-like" or "caudex-like", is sometimes used to mean "pachycaul", meaning "thick-stemmed". See also Caudex
Caulescent
Having a leafy stem above ground, as contrasted with Acaulescent and Scapose.
Cauline
Borne on an aerial stem, e.g. leaves, flower or fruits (when applied to the latter two organs, usually referring to older stems; = cauliflorous).
Chasmogamous
Of flowers that are pollinated when the perianth is open. see Cleistogamous.
Cilia
(singular cilium, adjective ciliate) Generally, hairs more or less confined to the margins of an organ, like eye-lashes; in motile cells, minute, hair-like protrusions which aid motility.
Circumscissile
Describing any seed-vessel that splits along a circumference, with the upper part coming off as a lid.
Clambering
A plant growing more or less erect by leaning or twining on another structure for support, or by clinging with tendrils.
Clasping
A leaf without a petiole and whose base partially or completely surrounds a stem.
Claw
Narrow, stalk-like basal portion of petal, sepal of bract.
Cleft
Deeply cut about halfway to the midrib, as in many leaves and petals.
Cleistogamous
Of flowers that self-pollinate and never open fully, or self-pollinate before opening; see Chasmogamous.
Climber
A plant growing more or less erect by leaning or twining on another structure for support, or by clinging with tendrils.
Columnar
Shaped like a column.
Community
An assemblage, in nature, of plants that characteristically occur together.
Compound
Composed of several parts, for instance a leaf with leaflets, a gynoecium with several carpels, or an inflorescence made up of smaller inflorescences.
Cone
A fruit, usually woody, ovoid to globular, including scales, bracts or bracteoles arranged around a central axis, e.g. in gymnosperms, especially conifers and Casuarina.
Conifer
Conifers are gymnosperms, non-flowering plants; cone-bearing seed plants; woody, mostly trees, some shrubs. Today, all living conifers belong to the order Pinales within the Pinopyta Division.
Connate
Fused to another organ (or organs) of the same kind; e.g. petals in a floral tube; compare Adnate and Caudex.
Cordate
Heart-shaped, with the notch lowermost; of the base of a leaf, like the notched part of a heart.
Coriaceous
Leathery; stiff and tough, but somewhat flexible.
Corm
Fleshy, swollen stem base, usually underground, storing food reserves, with buds naked or covered by very thin scales; a type of rootstock. Adjectives derived from "corm" include "cormose" and "cormous";.
Corolla
Collective term for the petals of a flower.
Corona
(adjective: coronate) literally, crown 1. in flowering plants, ring of structures that may be united in a tube, arising from the corolla or perianth of a flower and standing between the perianth lobes and the stamens. The trumpet of a daffodil is a corona. 2. in grasses, a hardened ring of tissue surmounting the lemma in some species.
Corymb
(Adjective corymbose) inflorescence with branches arising at different points but reaching about the same height, giving the flower cluster a flat-topped appearance.
Crenate
Leaf or fruit with blunt, rounded teeth or scalloped margin.
Crenulate
Minutely scalloped.
Crisped
Finely curled. A term generally applied to the edges of leaves and petals.
Cruciform
Cross-shaped.
Culm
In grasses, sedges, rushes, and some other monocotyledons, an aerial stem bearing the inflorescence; strictly, from the base of the plant to the lowest involucral bract (or base of the inflorescence).
Cultivar
The term cultivar is derived from cultivated variety and denotes an assemblage of cultivated plants clearly distinguished by one or more characters (morphological, physiological, cytological, chemical or other); when reproduced (sexually or asexually), the assemblage retains its distinguishing characters. A cultivar may arise in cultivation or be introduced from the wild. It is a variant of horticultural interest or value. Cultivar names are written with single quotation marks around them e.g. 'Blue Carpet', 'Alba'. All new names established after 1 January 1959, must be in common language (that is, not in Latin) but names established in Latin prior to this date are retained in Latin form.
Cuneate
Wedge-shaped; with straight sides converging at base. See Leaf shape.
Cyathia
Plural of cyathium
Cyathium
An inflorescence of unisexual flowers surrounded by involucral bracts, esp. the flowers of Euphorbia.
Cyme
(Adjective cymose) Inflorescence in which the main axis (central stem) and all lateral branches end in a flower, terminal flower develops first (each lateral may be repeatedly branched.
Cypsela
A dry, indehiscent, one-seeded fruit formed from an inferior ovary.

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Deciduous
Falling seasonally, for instance bark, leaves, petals; compare Persistent
Decompound
Divided to more than one level, as in bipinnate leaves for example, in which the leaflets of what otherwise would be a pinnate leaf, are themselves pinnately divided
Decumbent
Plants or plant parts with branches growing horizontally but turned or curving up at the extremity.
Decurrent
Extending downwards beyond the point of insertion e.g. when the base of a leaf or a fungal gill is prolonged downwards along the stem in a raised line or narrow wing.
Decussate
Opposite, with successive pairs borne at right angles to the last; generally applied to the arrangement of leaves.
Deflexed
Bent downwards; compare inflexed.
Dehiscence
(Dehiscent) Splitting at maturity along a built-in line of weakness.
Deltoid
With the shape of the uppercase Greek letter Δ, i.e. like a more or less equilateral triangle. See Leaf shape.
Dentate
Toothed, botanically used to describe leaf margins.
Dichotomous
Forking into two equal branches. This may result from an equal division of the growing tip, or may be sympodial, in which the growing tip is aborted and replaced. Typically refers to mode of branch growth, as in Aloe dichotoma, but also to other organs, such as the thorns of various species of Carissa (which morphologically are branches) and thalli or hyphae of various algae and fungi.
Diffuse
Spreading widely and loosely.
Dioecious
Of plant, when male and female reproductive structures develop on different individuals; of inflorescence, male and female flowers in separate inflorescence’s; compare Monoecious
Disk or Disc
A plate or ring of structures derived from the receptacle, and occurring between whorls of floral parts: in daisies, the central part of capitulum, hence disk flowers or florets.
Discoid
Resembling a disc or plate, having both thickness and parallel faces and with a rounded margin. Also used to describe the flower head of Compositae where there are no ray florets, but only disc florets.
Disjunct
Occurring in widely separated geographic areas, distinctly separate; applies to a discontinuous range in which one or more populations are separated from other potentially interbreeding populations far enough as to preclude gene flow between them.
Dissected
Deeply divided; cut into many segments.
Distal
Remote from the point of origin or attachment; the free end; compare Proximal.
Diurnal
Of the day; occurring or opening in the daytime.
Divaricate
Wide-spreading.
Divergent
Spreading in different directions, generally upward.
Drupe
A succulent fruit formed from one carpel; the single seed is enclosed by a stony layer of the fruit wall; kernel; e.g. peaches and olives.

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Elliptical (elliptic)
Shaped like a flattened circle, symmetrical about both the long and the short axis; about twice as long as broad, tapering equally both to the tip and the base; oval.
Endemic
Having a natural distribution restricted to a particular geographic region; see Native.
Entire
1. not divided. 2. (of a margin) having a smooth margin, not lobed or toothed (it may be wavy or scalloped).
Ephemeral
Short-lived.
Epipetalous
Of stamens that are attached to the petal.
Erect
Upright, more or less perpendicular to the ground or point of attachment.
Estivate
A period of reduced metabolic rate (dormancy) for reptiles and small mammals to avoid long dry hot summers.
Exserted
Projected beyond, e.g. the stamens beyond the corolla tube.
Extinction, local or extirpated
Local extinction, or extirpation, is the condition of a species (or other taxon) that ceases to exist in the chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinctions.

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Farinaceous
Powderiness that is mealy
Farinose
(adjective farinaceous) Floury, covered with meallike particles, as often seen in Chenopoidum (Amaranthaceae).
Fascicle
(adjective fasciculate) In botany a cluster or bundle of leaves or flowers growing crowed together, e.g. a tuft of leaves all arising from the same node such as pine needles.
Filament
1. Stalk of a stamen. 2. Thread, one or a few cells thick.
Filiform
Thread-like. Pertaining to leaf shapes.
Filiferous
Bearing threads, as sometimes the leaf margin.
Fissure
A split or crack, often referring to fissured bark; also, a line or opening of dehiscence.
Floccose
With a soft and woolly covering of hairs.
Floret
Literally a small flower, but usually refers to the individual true flowers clustered within an inflorescence, particularly in inflorescences of the daisy and grass families.
Follicle
A dry fruit formed from one carpel, splitting along a single suture, to which the seeds are attached; compare; Pod (of legume).
Funnelform
With a form gradually widening from the base to apex; funnel-shaped; compare Salverform.
Forb/herb
Vascular plant without significant woody tissue above or at the ground. Forbs and herbs may be annual, biennial, or perennial but always lack significant thickening by secondary woody growth and have perennating buds borne at or below the ground surface.
Fruit
Seed-bearing structure in angiosperms formed from the ovary, and sometimes associated floral parts, after flowering.
Fugacious
Disappearing, falling off, or withering; compare Persistent and Caducous.
Fusiform
Rod-shaped and narrowing gradually from the middle towards each end; spindle-shaped.

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Glabrous
Without surface ornamentation such as hairs, scales or bristles.
Glabrescent, Glabrate
Becoming glabrous, hairless, or smooth; glabrate. Becoming glabrous, almost glabrous.
Glaucous
Botanical adjective, leaves or other herbage that is bluish-grey or green which describes the pale grey or bluish-green appearance of the surfaces of some plants.
Gland
A secretory structure within or on the surface of a plant; (loosely) a smooth, usually shining, bead-like outgrowth.
Glandular hair
Hairs tipped with a gland.
Globose, Globular
Spherical. See also Subglobose.
Globulose
Small or nearly spherical.
Glochid
A barbed hair or bristle, e.g. the fine hairs in Opuntia.
Glutinous
Sticky, gummy, gluelike. See also Viscid.
Gymnosperm
A seed-bearing plant with unenclosed ovules borne on the surface of a sporophyll; includes, among others, conifers, Ginkgo, Gnetum and cycads. From gymno = naked, exposed; compare angio = covered, enclosed.

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Halophyte
A plant adapted to living in highly saline habitats; a plant that accumulates high concentrations of salt in its tissues; compare Xerophyte.
Hastate
Leaf description, narrow and pointed but abruptly enlarged at the base into two acute diverging lobes; may refer only to the base of a leaf with such lobes; compare Sagittate.
Helicoid
Coiled; of a cymose inflorescence, when the branching is repeatedly on the same side (the apex is often recurved); see Scorpioid.
Herb
A plant species lacking woody tissue when mature.
Herbaceaus
Not woody; usually green, and soft in texture.
Hirsute
Bearing coarse, rough, longish hairs. See Indumentum.
Hispid
Having long erect rigid hairs or bristles, harsh to touch.
Holotype
The single specimen designated as the type of a species by the original author at the time the species name and description was published. Also see Lectotype
Hypanthium
A tube or cup-like structure in a flower that includes the bases of sepals, petals, and stamens, and may or may not be connected (adnate) to the ovary.

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Imbricate
Overlapping each other; of perianth parts, edges overlapping in the bud (the convoluted arrangement is a special form of imbrication.
Imparipinnate
A pinnate leaf with an odd number of pinnae (terminated by a single leaflet); compare Paripinnate.
Indehiscent
Not opening in any definite manner at maturity; usually referring to fruit. Contrast with degiscent.
Indigenous
Native to the area; its presence in that region is the result of only natural processes with no human intervention; not introduced and not necessarily confined to the region discussed (hardly distinct from ‘native’ but usually applied to a smaller area). The term is equivalent to "native" in less scientific usage. For example, the Joshua Tree (Yucca brevifolia) is native to parts of the southwest but indigenous to Joshua National Park, California. Compare; Endemic; Native.
Indumentum
A collective term for a surface covering of any kind of trichomes, e.g. hairs, scales.
Inflorescence
Several flowers closely grouped together to form an efficient structured unit; the grouping or arrangement of flowers on a plant.
Involucre
A structure surrounding or supporting, usually a head of flowers. In Asteraceae, it is the group of phyllaries (bracts) surrounding the inflorescence before opening, then supporting the cup-like receptacle on which the head of flowers sits. In Euphorbiaceae it is the cuplike structure that holds the nectar glands, nectar, and head of flowers, and sits above the bract-like cyathophyll structure.
Involute
Rolled inwards, for example when the margins of a leaf are rolled towards the adaxial (usually upper) surface; compare Revolute.
Irregular
Cannot be divided into two equal halves through any vertical plane. See also Asymmetrical, compare Zygomorphic, Actinomorphic, Regular.

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[K]    ↵ Return to top

[L]    ↵ Return to top

Lanceolate
Lance-shaped, long, wider in the middle.
Laciniate
Of lobes; with ends irregularly divided into deeply divided, narrow, pointed segments; Of margins; deeply divided into pointed segments in an irregular manner.
Leaflet
The ultimate segments of a compound leaf.
Lectotype
A specimen chosen by a later researcher to serve as if it were the holotype (specimen designated in the original description). It is chosen from among the specimens available to the original publishing author (the isotypes, syntypes and/or paratypes) of a scientific name when the holotype was either lost or destroyed, or when no holotype was designated. Also see Holotype.
Legume
1. a fruit characteristic of the family Fabaceae, formed from one carpel and either dehiscent along both sides, or indehiscent.
2. a crop species in the family Fabaceae.
3. a plant belonging to the Fabaceae family).
Lepidote
Covered with small scales.
Liana
A woody climbing plant, rooted in the ground (liane is also used). Also see Scandent and Vine.
Ligulate
1. Bearing a ligule.
2. Strap-shaped.
Ligule
1. Small membranous appendage on the top of the sheath of grass leaves.
2. A minute adaxial appendage near the base of a leaf, e.g. in Selaginella.
3. Extended, strap-like corolla of some daisy florets. See Ligulate.
Limestone
A sedimentary rock (CaCO3), composed mostly of skeletal fragments of marine organisms such as coral, forams and molluscs. Its major materials are the minerals calcite and aragonite, which are different crystal forms of calcium carbonate (CaCO3). see Calcareous Calcareous and Caliche Caliche.
Linear
Very narrow in relation to its length, with the sides mostly parallel.
Lobe
Part of a leaf (or other organ), often rounded, formed by incisions to about halfway to the midrib.
Lobulate
With small lobes or shallowly lobed.
Lomentum
A pod-like indehiscent legume fruit that develops constrictions between the segments and at maturity breaks into one-seeded segments.
Lyrate
Lyre-shaped; deeply lobed, with a large terminal lobe and smaller lateral ones.

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Margin
The edge, as in the edge of a leaf blade.
Mericarp
One segment of a fruit (a schizocarp) that splits at maturity into units derived from the individual carpels, or a carpel, usually 1-seeded, released by the break-up at maturity of a fruit formed from 2 or more joined carpels. (see Schizocarp).
Midrib
The central, and usually most prominent, vein of a leaf or leaf-like organ; see Midvein.
Midvein
see Midrib.
Monocarpic
Flowering and setting seed only once before dying.
Monoecious
Having the stamens and the pistils in separate flowers on the same plant; compare Dioecious.
Monotypic
Containing only one taxon of the next lower rank, e.g. a family with only one genus, or a genus that includes only a single species.

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Native
Naturally occurring in an area, but not necessarily confined to it; see Endemic.
Naturalized
Describing a plant, introduced from another region, that grows and reproduces readily in competition with the natural flora.
Nectar
A (usually sweet) fluid produced by the flowers of many plants, collected by bees and other insects.
Nectary
(adjective nectariferous) a specialized gland that secretes nectar.
Nocturnal
Botany: Opening at night; used of flowers.
Node
The part of a stem where leaves or branches arise.
Nut
A hard, dry, indehiscent fruit, containing only one seed.
Nutlet
Nutlet (A small nut, one of the lobes or sections of the mature ovary of some members of the Boraginaceae, Verbenaceae, and Lamiaceae.

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Obconic
Of a fruit, hypanthium, pistil or calyx structure; an inverted cone shape, attached at apex.
Oblanceolate
Leaf shape; top wider than bottom.
Oblong
Length a few times greater than width, with sides almost parallel and ends rounded.
Obovate
Of a leaf, a 2-dimensional shape of which the length is about 1.5 times the width, and widest above the center.
Obovoid
Botany; Egg-shaped and solid, with the narrow end at the base: an obovoid fruit.
Obtuse
Blunt or rounded at the tip or apex; converging edges making an angle of more than 90°; compare Acute. See Leaf shape.
Ochrea
(ocrea, ochrea) A sheath, formed from two stipules, encircling the node in Polygonaceae.
Opposite
Leaves or flowers borne at the same level but on opposite sides of the axis; or (as verb) when something occurs on the same radius as something else, for example anthers opposite sepals; compare Alternate.
Orbicular
Flat and more or less circular.
Ovate
Shaped like a section through the long-axis of an egg and attached by the wider end.
Ovoid
Egg-shaped, with wider portion at base; 3-dimensional object, ovate in all sections through long-axis.

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Palmate
1. leaf with veins radiating out from a central point (usually at the top of a petiole), resembling spread out fingers pointing away from the palm. 2. A compound palmate leaf has leaflets that radiate from a central point (usually at the top of a petiole).
Palmatifid
Deeply divided into several lobes arising from more or less the same level.
Palmatisect
Intermediate between palmate and palmatifid, i.e. the segments are not fully separated at the base; often more or less digitate.
Panicle
(adjective paniculate) a compound raceme; an indeterminate inflorescence in which the flowers are borne on branches of the main axis or on further branches of these.
Papilla
(plural papillae, adjective papillose, papillate) a small, elongated protuberance on the surface of an organ, usually an extension of one epidermal cell.
Pantropical
In biogeography, a pantropical ("across the tropics") distribution is one which covers tropical regions of all continents. The genera Acacia is one example.
Pappus
In daisy florets, a tuft or ring of hairs or scales borne above the ovary and outside the corolla (representing the missing calyx); a tuft of hairs on a fruit.
Paripinnate
Having an even number of leaflets (or pinnae), that is terminated by a pair of pinnae as opposed to a single pinna; compare Imparipinnate.
Pedicel
A pedicel is a stem that attaches single flowers to the inflorescence. It is the branches or stalks that hold each flower in an inflorescence that contains more than one flower. The stem or branch from the main stem of the inflorescence that holds a group of pedicels is called a peduncle.
Peduncle
A stalk supporting an inflorescence, which is the part of the shoot of seed plants where flowers are formed.
Pellucid
Transmitting light; for example, said of tiny gland dots in the leaves of e.g. Myrtaceae and Rutaceae that are visible when held in front of a light.
Pendulous
Hanging loosely or freely, suspended so as to swing freely, to sway.
Pepo
A type of berry formed from an inferior ovary and containing many seeds, usually large with a tough outer skin, for instance, pumpkin, cucumber.
Perennial
A plant whose life span extends over several years.
Perfect
A "perfect" flower has both stamens and carpels, and may be described as bisexual; See Bisexual.
Perfoliate
With its base wrapped around the stem (so that the stem appears to pass through it), e.g. of leaves and bracts.
Persistent
Remaining attached to the plant beyond the usual time of falling, for instance sepals not falling after flowering, flower parts remaining through maturity of fruit; compare Deciduous, Caducous.
Petal
In a flower, one of the segments or divisions of the inner whorl of non-fertile parts surrounding the fertile organs, usually soft and conspicuously coloured; compare; Sepal.
Petaloid
Like a petal; soft in texture and coloured conspicuously.
Petiolate
Subtended by a petiole.
Petiole
The stalk of a leaf.
Petiolule
The stalk of a leaflet.
Perianth
Parts of the flower; collective term for the petals (corolla) and sepals (calyx), particularly when both are very similar in appearance; compare Tepal.
Phyllary (plural phyllaries)
An individual bract within an involucre or involucel.
Pilose
Covered with soft, weak, thin and clearly separated hairs, which are usually defined as long and sometimes ascending.
Pinna
(Plural pinnae) a primary segment of a compound leaf.
Pinnate
A compound leaf with leaflets arranged on each side of a common petiole or axis; also applied to how the lateral veins are arranged in relation to the main vein. See pinnately.
Pinnately
In a pinnate fashion (comparative more pinnately, superlative most pinnately)
Pinnately lobed
A simple leaf with rounded or pointed lobes on each side of the midrib or central and most prominent vein of a leaf or leaf-like organ.
Pinnatifid
Having lobes with incisions that extend less than half-way toward the midrib. (Wiki usage notes, deeper incisions are pinnatipartite. Incisions reaching nearly to the midrib are pinnatisect.)
Pinnatipartite
Having lobes with incisions that extend more than half-way, or up to the midrib.
Pinnatisect
Having lobes with incisions reaching nearly to the midrib are pinnatisect. (Wiki usage notes, less deep incisions are pinnatifid.)
Pinnule
Ultimate free division (or leaflet) of a compound leaf, or a pinnate subdivision of a multipinnate leaf.
Pistil
1. A single carpel when the carpels are free. 2. A group of carpels when the carpels are united by the fusion of their walls.
Pistillate
(of a plant or flower) having pistils but no stamens.
Plumose
Like a feather; with fine hairs branching from a main axis.
Pod
1. a legume, the fruit of a leguminous plant, a dry fruit of a single carpel, splitting along two sutures. 2. siliqua and silicula, the fruit of Brassicaceae, a dry fruit composed of two carpels separated by a partition.
Pome
A fruit that has developed partly from the ovary wall but mostly from the hypanthium, e.g., apple.
Prickle
(adjective: prickly) hard, pointed outgrowth from the surface of a plant (involving several layers of cells but not containing a vein); sharp outgrowth from the bark, detachable without tearing wood; cf. thorn.
Procumbent
Spreading along the ground but not rooting at the nodes: not as close to ground as Prostrate
Prostrate
Lying flat on the ground. See Procumbent
Proximal
Near the point of origin or attachment. See Distal
Pseudanthium
A particular form of inflorescence occurring in the Asteraceae and Euphorbiaceae, in which multiple flowers are grouped together to form a flower-like structure, commonly called a head or capitulum.
Puberulous (puberulent)
Covered with minute soft erect hairs.
Pubescent
Downy; covered with short, soft, erect hairs.

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Raceme
An unbranched flowering stem (inflorescence), continuously growing with flowers containing short stems (pediciles) along its axis.
Rachis
(plural rachises; rachides) the axis of an inflorescence or a pinnate leaf; for example ferns; secondary rachis is the axis of a pinna in a bipinnate leaf distal to and including the lowermost pedicel attachment.
Radial
With structures radiating from a central point as spokes on a wheel, for example, the lateral spines of a cactus.
Radiate
Radical
Springing from the root; clustered at base of stem.
Of daisies, of a capitulum, with ray florets surrounding disc florets.
Ray
1. Zygomorphic (ligulate) flowers in a radiate flowerhead, that is, ray-florets/flowers, for example Asteraceae.
2. Each of the branches of an umbel.
Receptacle
The axis of a flower, in other words, floral axis; torus; for example in Asteraceae, the floral base or common receptacle is the expanded summit of the peduncle on which the flowers are inserted.
Regular
See Actinomorphic.
Reniform
Kidney-shaped.
Retrorse
(adverb retrorsely) Bent backwards or downwards. See also Antrorse.
Revolute
Rolled under (downwards or backwards), for example when the edges of leaves are rolled under towards the midrib; compare Involute.
Rhizome
A perennial underground stem usually growing horizontally. See also Stolon.
Rhombic
Like a rhombus: an oblique figure with four equal sides; compare trapeziform, trullate.
Rhomboid
A four-sided figure with opposite sides parallel but with adjacent sides an unequal length (like an oblique rectangle); See also Rhombic
Rose hip
Rose hip, rose haw or rose hep, is the fruit of the rose plant, usually red-to-orange, but ranges from dark purple to black in some species.
Rosette
A rosette is a circular arrangement of leaves, with all the leaves at a similar height. Though rosettes usually sit near the soil, their structure is an example of a modified stem.
Rotate
Circular and flattened; for example a corolla with a very short tube and spreading lobes (for instance some Solanaceae))
Runcinate
Sharply pinnatifid or cleft, the segments directed downward.

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Sagittate
Leaf description, shaped like the head of an arrow; narrow and pointed but gradually enlarged at base into two straight lobes directed downwards; may refer only to the base of a leaf with such lobe; compare Hastate.
Saline soil
Soils containing high levels of salts from natural conditions, or from agricultural practices, so as to negatively impact successful plant growth.
Salverform
Trumpet-shaped; with a long, slender tube and a flat, abruptly expanded limb; compare Funnelform.
Samara
A dry, indehiscent fruit with its wall expanded into a wing, e.g. Maple trees (Acer).
Scabrid (scabrous)
Rough to the touch with short hard emergences or hairs.
Scale
1. a reduced or rudimentary leaf, for example around a dormant bud.
2. a flattened epidermal outgrowth, such as those commonly found on the leaves and rhizomes of ferns.
Scandent
Climbing, by whatever means. Also see Vine and Liana.
Scape
(adjective scapose) A stem-like flowering stalk of a plant with radical leaves.
Scapose
Having the floral axis more or less erect with a few leaves or devoid of leaves; consisting of a scape.
Scarious
Of plant parts or surfaces that may be stiff or scaly, dry membranous appearance, shriveled, they are often not green in color but yellowish, whitish or brownish.
Schizocarp
A dry fruit formed from more than one carpel but breaking apart into individual carpels (mericarp) when ripe.
Scorpioid
(Botany) Resembling a scorpion's tail, as in a scorpioid cyme; circinate; of a cymose inflorescence, when it branches alternately on one side and then the other; compare Helicoid.
Serrate
Toothed with asymmetrical teeth pointing forward; like the cutting edge of a saw.
Serrulate
Finely serrate.
Semiterete
(or semi-terete), rounded on one side, but flat on the other; compare Terete.
Sepal
In a flower, one of the segments or divisions of the outer whorl of non-fertile parts surrounding the fertile organs, usually green; compare petal; compare Petal.
Sessile
Without a stalk, e.g. of a stigma, when the style is absent or a leaf without a stalk.
Sheathing
Leafy rolled or tubular structure on the lower part of a leaf; clasping or enveloping the stem, most often on sedges or grasses.
Shrub
Silicle
A fruit (seed capsule) of 2 fused carpels with the length less than three times the width. When the length is greater than three times the width of the dried fruit it is referred to as a silique; compare Silique.
Silique
A fruit (seed capsule) of 2 fused carpels with the length being more than three times the width. When the length is less than three times the width of the dried fruit it is referred to as a silicle; compare Silicle.
Simple
Undivided, for instance a leaf not divided into leaflets (note, however, that a simple leaf may be entire, toothed or lobed) or an unbranched hair or inflorescence.
Sinuate
With deep, wave-like depressions along the margins, but more or less flat; compare undulate. compare Undulate.
Solitary
Single, of flowers that grow one plant per year, one in each axil, or widely separated on the plant; not grouped in an inflorescence.
Spathe
(adj. spathaceous), a large bract ensheathing an inflorescence. Traditionally any broad flat blade.
Spathulate (spatulate)
Spoon-shaped; broad at the tip with a narrowed projection extending to the base.
Spike
(adjective spicate) an unbranched, indeterminate inflorescence in which the flowers are without stalks; cf. raceme.
Spine
(adjective spinose) a stiff, sharp structure, formed by the modification of a plant organ that contains vascular tissue; e.g. a lateral branch or a stipule; includes thorns.
Spinescent
Ending in a spine; modified to form a spine.
Spreading
Extending horizontally, for example branches; standing out at right angles to axis, for example leaves or hairs.
Stalk
The supporting structure of an organ, usually narrower in diameter than the organ.
Stamen
(adjective staminate) Male organ of a flower, consisting (usually) of a stalk (Filament) and a pollen-bearing portion (Anther).
Staminate
(of a plant or flower) having stamens but no pistils.
Stellate
Star-shaped, for example a type of hair.
Stigma
The pollen-receptive surface of a carpel or group of fused carpels, usually sticky; usually a point or small head at the summit of the style.
Stipitate
Stalked; borne on a stipe; of an ovary, borne on a gynophore.
Stipulate
Bearing stipules.
Stipule
Small appendage at the bases of leaves in many dicotyledons.
Stolon
Slender, prostrate or trailing stem, producing roots and sometimes erect shoots at its nodes. See also Rhizome.
Strigose
Having stiff, straight, closely appressed hairs or bristles: strigose leaves.
Style
An elongated part of a carpel, or group of fused carpels, between the ovary and the stigma.
Subglobose
Inflated, but less than spherical. See also Globose.
Subshrub
Low-growing shrub usually under 0.5 m (1.5 feet) tall, never exceeding 1 meter (3 feet) tall at maturity. Applies to vascular plants only. A dwarf-shrub in the FGDC classification.
Subtend
To stand beneath or close to, as in a bract at the base of a flower.
Subulate
Very narrow, linear, and tapering gradually from the base to a fine point, awl-shaped.
Suffrutescent
Comparative more suffrutescent, superlative most suffrutescent. Slightly woody or shrubby at the base. Subshrub or undershrub.
Suffrutex
A subshrub.
Symmetrical
Capable of being divided into at least two equal, mirror-image halves (e.g. zygomorphic) or to have rotational symmetry (e.g. regular, actinomorphic). Contrast with irregular, asymmetrical.
Sympatric
With more or less similar or overlapping ranges of distribution.
Sympetalous
With united (connate or fused) petals.
Capable of being divided into at least two equal, mirror-image halves (e.g. zygomorphic) or to have rotational symmetry (e.g. Regular, Actinomorphic). Contrast with Irregular, Asymmetrical.

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Tendril
A slender organ (modified e.g. from stem, leaf, leaflet or stipule) used by climbing plants to cling to an object.
Tepal
Part of a flower or perianth segment, either sepal or petal; usually used when the parts of the perianth are difficult to distinguish, e.g. the petals (caylx) and sepals (corolla) share the same color, or the petals are absent and the sepals are colorful.
Terete
Circular in cross-section; more or less cylindrical without grooves or ridges; compare Semiterete.
Terminal
Situated at the tip or apex.
Ternate
In groups of three; of leaves, arranged in whorls of three; of a single leaf, with the leaflets arranged in groups of three.
Thorn
A sharp, stiff point, usually a modified stem, that cannot be detached without tearing the subtending tissue; a spine; cf. prickle.
Tree
Trichomes
In non-filamentous plants, any hair-like outgrowth from epidermis, e.g. a hair or bristle; sometimes restricted to unbranched epidermal outgrowths.
Trifoliolate or Trifoliate
A compound leaf of three leaflets, for example a clover leaf.
Truncate
Cut off squarely; with an abruptly transverse end.
Tomentose
Leaf or other surfaces covered in dense, soft, often matted short hairs, sometimes woolly.
Tubercle
A small wart-like outgrowth.
Tunicate
Having successive, close-fitting concentric coats, as in an onion bulb.

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Umbel
(adjective umbellate) A racemose inflorescence in which all the individual flower stalks arise in a cluster at the top of the peduncle and are of about equal length; in a simple umbel, each stalk is unbranched and bears only one flower; a cymose umbel is an apparent umbel but its flowers open centrifugally.
Undulate
Wavy and not flat; compare Sinuate.
Unispecific
Of one species; monospecific; such as the former Cuscutaceae Family containing the single genus Cuscuta.
Unispexual
Of one sex; bearing only male or only female reproductive organs, dioecious, dioicous. See Sexual reproduction in plants.
Urceolate
Urn-shaped.
Utricle
A small bladder; a membranous bladder-like sac enclosing an ovary or fruit; in sedges a fruit in which the pericarp is larger than, and loosely encloses, the seed.

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Variegated
Irregularly marked with blotches or patches of another color.
Velutinous
Velvety texture due to minute moderately firm hairs or scales of various lengths.
Velvety
Densely covered with fine, short, soft, erect hairs.
Venation
The arrangement of veins in a leaf.
Villous
Abounding in or covered with long, soft, straight hairs; shaggy with soft hairs.
Vine
A plant that climbs by means of trailing, twining stem or runner. Also see Scandent and Liana.
Viscid
Sticky; coated with a thick, syrupy secretion.

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Whorl
A ring of organs borne at the same level on an axis, for example leaves, bracts or floral parts.

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Xerophyte
A plant generally living in a dry habitat, typically showing xeromorphic or succulent adaptation; a plant able to tolerate long periods of drought; compare Halophyte.

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Zygomorphic
Bilaterally symmetrical; symmetrical about one vertical plane only; applies to flowers in which the perianth segments within each whorl vary in size and shape; compare Actinomorphic, Irregular.
References:
Wikipedia contributors, 'Glossary of botanical terms', Wikipedia, The Free Encyclopedia, 20 April 2015, 19:23 UTC,
http://en.wikipedia.org/w/index.php?title=Glossary_of_botanical_terms&oldid=657370054
https://en.wikipedia.org/wiki/ - Definitions