Glossary of Taxonomic Terminology

Courtesy of Dr. Bert McCarty and Dr. David Hall.

A
  • Axis: Axis is themain stem of an inflorescence especially of a panicle.
  • Axillary Bud: Axillary bud is a bud located in the leaf axil.
  • Axil: Axil is an angle between the leaf and stem.
  • Awn: Awn is a slender or stiff bristle usually extending from a grass floret specifically the glumes or lemma.
  • Auricle: Auricle are small ear-shaped lobes or appendages at the junction of the leaf sheath and blade in grasses or at the leaf base of broadleaf plants.
  • Atypical: Atypical means unusual not the norm.
  • Attenuate: Attenuate means gradually becoming very narrow and slender.
  • Asymmetrical: Asymmetrical means lop-sided; having two sides different in shape or area.
  • Asexual: Asexual is reproduction not involving the fusion of a sperm and an egg.
  • Ascending: Ascending means sloping or growing upward or outward but not straight.
  • Articulate: Articulate means jointed.
  • Aquatic: Aquatic means growing in water.
  • Appressed: Appressed means pressed flatly and closely against the surface.
  • Apomixis: Apomixis is seed production without fertilization.
  • Apical: Apical means at the apex.
  • Apex: Apex is the tip of a stem root or leaf.
  • Apetiolate: Apetiolate means lacking a petiole.
  • Anthesis: Anthesis is an opening of the flower bud; when pollination occurs.
  • Anther: Anther is a sac-like portion of the male part of a flower (stamen) that bears pollen.
  • Annual: Annual is a plant starting from a seed completing its life cycle and dying within one year.
  • Angled: Angled means not rounded angular in cross-section.
  • Angiosperms: Angiosperms are plants with seeds enclosed in an ovary.
  • Alternate: Alternate is an arrangement of a single leaf bud or branch attached singly at different points on the stem; appearing to alternate.
  • Aggregate: Aggregate means collected together in tufts groups or bunches.
  • Aerial: Aerial are plants or parts of plants living above the surface of the ground or water.
  • Adventitious Root: Adventitious root is a root originating in an unusual or unexpected place such as from stem or leaf tissue.
  • Adventitious Bud: Adventitious bud is a bud produced in an unusual or unexpected place for example near a point of stem injury or on a leaf or a root.
  • Adaxial: Adaxial is located toward the axis side for example the upper side of a leaf.
  • Acute: Acute means sharply pointed.
  • Acuminate: Acuminate is a tip gradually tapering to a point with the margins curving inward.
  • Achene: Achene is a small dry one-seeded fruit which does not open or split at maturity; i.e. sunflower seed.
  • Abaxial: Abaxial is located away the axis side for example the underside of a leaf.
B
  • Bur: Bur is a rough prickly seed capsule.
  • Bulblet: Bulblet is a small bulb see bulbil.
  • Bulbil: Bulbil is a small bulb or bulblike structure usually borne in leaf axils or among or in the place of flowers or in other unusual places. It can fall off and grow into a new plant.
  • Bulb: Bulb is an underground short thickened shoot where food is stored such as wild onion.
  • Bud: Bud is an usually tightly bunched undeveloped shoot or flower usually located in a leaf axil or at the tip of a stem or branch.
  • Bristle: Bristle is a short coarse stiff hairlike part.
  • Branch: Branch is a lateral stem.
  • Bract: Bract is a modified usually reduced leaf associated with a flower or flower cluster.
  • Brackish: Brackish means somewhat salty.
  • Boat-Shaped: Boat-Shaped are leaf tips which are shaped like the front (or bow) of a boat such as species of Poa.
  • Blade: Blade is the expanded usually flat portion of a leaf.
  • Bisexual: Bisexual are flowers with male (stamens) and female (pistil) elements.
  • Bipinnate: Bipinnate are two rows of lateral branches along an axis which are again divided into two rows; feather-like.
  • Biotype: Biotype is a population within a species that has distinct genetic variation.
  • Bilateral: Bilateral means capable of division into only one plane forming two equal parts.
  • Biennial: Biennial is a plant that completes its life cycle and dies in two years. The first year seeds germinate forming vegetative growth. The second year flowering seed set and death occur.
  • Berry: Berry is fleshy fruit with many seeds rather than a central stone; i.e. tomato.
  • Bearded: Bearded means having long hairs.
  • Beak: Beak is a hard point or projection especially with seeds and fruit.
  • Base: Base is the basal or lower part of a plant or organ.
  • Basal Rosette: Basal Rosette is a cluster of leaves radiating at the base of a plant at ground level.
C
  • Cylindrical: Cylindrical means cylinder-shaped.
  • Cyathium: Cyathium is a small cup-like inflorescence structure of the Euphorbiaceae.
  • Cutin: Cutin is a waxy substance found on the surface of certain seeds or leaves to conserve water.
  • Cuticle: Cuticle is the waxy outer layer of a plant shoot.
  • Cuneate: Cuneate means wedge-shaped.
  • Cultivar: Cultivar is a horticultural variety or race that only persists under cultivation.
  • Culm: Culm is a flowering stem of a grass plant not including the leaves.
  • Crown: Crown is a meristematic growing point at or just below the ground where stems and roots join and new shoots emerge.
  • Crenate: Crenate is a type of leaf margin that is shallowly round-toothed or scalloped.
  • Cotyledon: Cotyledon is a seed leaf of the embryo most often a storage site of reserve food used by germinating seedlings.
  • Corymb: Corymb is the flat-topped open inflorescence of stalked flowers outer flowers having longer stalks than inner ones.
  • Corona: Corona is crown-like ring often showy between petals and stamens.
  • Corolla: Corolla are all the flower petals.
  • Corm: Corm is a stout short vertical bulblike underground food storage stem.
  • Cordate: Cordate means heart-shaped with the point at the terminal end.
  • Conical: Conical means cone-shaped.
  • Compressed: Compressed means flattened laterally.
  • Compound Leaf: Compound leaf is a type of leaf composed of two or more distinct similar parts called leaflets.
  • Composite: Composite is a member of the Compositae or Asteraceae family that has a dense inflorescence usually composed of florets a receptacle and bracts.
  • Collar: Collar is the outer side of a grass leaf at the junction of the blade and sheath.
  • Coleoptile: Coleoptile is the protective sheath covering the shoot tip and leaves of emerging grass seedlings.
  • Clump-Forming: Clump-forming or tufted means growing in compact basal clusters.
  • Club-Shaped: Club-Shaped means cylindrical but swollen or becoming wider towards the top.
  • Cleft: Cleft means divided partway down.
  • Clavate: Clavate means club-shaped.
  • Clasping: Clasping is a type of leaf attachment where the leaf base partly or completely encircles the stem.
  • Ciliate: Ciliate means fringed with hairs on the margin; hairy
  • Cepitose: Cepitose are tufted or densely clumped stems.
  • Caryopsis: Caryopsis is the grass fruit normally dry at maturity consisting of a single seed with the seed coat united to the seed (ripened ovary).
  • Carpel: Carpel is a single unit of a pistil or ovary.
  • Capsule: Capsule is dry fruit splitting when dry into two or more parts often many-seeded.
  • Capitate: Capitate is found in a globular cluster or head.
  • Calyx: Calyx are outer parts (layer or whorl) of a flower composed of leaf-like parts called sepals.
  • Callus: Callus is a hard or tough swollen area.
D
  • Drupe: Drupe is a fleshy fruit with a central stony seed. Example: mango.
  • Dorsal: Dorsal means on the back away from the stem or axis.
  • Divided: Divided is a term meaning to cut to the base or to the midrib.
  • Divaricate: Divaricate is another term for spreading.
  • Distinct: Distinct is another term meaning to separate.
  • Distichous: Distichous means conspicuously two-ranked.
  • Dissected: Dissected means divided into numerous narrow segments or lobes.
  • Discrete: Discrete is another term meaning to separate.
  • Disc Flower: Disc Flower is a type of flower with a tubular shaped corolla that is found in a head as all or part of the complete flower of many members of the Asteraceae (Compositae) family.
  • Dioecious: Dioecious are separate male (stamens) and female (pistil) plants; unisexual.
  • Digitate: Digitate are branches arising from a common point resembling the fingers of a human hand.
  • Diffuse: Diffuse means loose and widely spreading.
  • Dicotyledon Dicot: Dicotyledon Dicot are broadleaf plants with two seed embryos (leaves) or cotyledons when it emerges from the soil; commonly these also have netted leaf veins showy flowers flower parts in 4's or 5's and can have secondary growth
  • Denticulate: Denticulate means with very small pointed teeth.
  • Dentate: Dentate is a type of leaf margin that is toothed with the teeth perpendicular to the leaf margin.
  • Deltoid: Deltoid means triangular-shaped.
  • Dehiscent: Dehiscent means splitting.
  • Decurrent: Decurrent is a type of leaf attachment where the leaf base or margin extends down the stem beyond the point of attachment
  • Decumbent: Decumbent means lying on the ground but rising at the tip.
  • Deciduous: Deciduous means falling off at the end of each growing season.
  • Day-Neutral Plants: Day-neutral plants are plants with no daylength requirements for floral initiation.
E
  • Extravaginal: Extravaginal means stem penetration growth through the basal leaf sheath such as rhizomes and stolons.
  • Exotic: Exotic means introduced from another country not native.
  • Exocarp: Exocarp is the outermost layer of the pericarp (fruit wall).
  • Evergreen: Evergreen is a term meaning retaining green leaves year-round.
  • Even-Pinnate: Even-Pinnate is a compound leaf with paired leaflets on opposite sides of the axis including the tip.
  • Epiphyte: Epiphyte is a plant rooted on another plant.
  • Epidermis: Epidermis is the outer cellular layer of plants which helps prevent drying and mechanical injury.
  • Epicotyl: Epicotyl is the young stem of a seedling or embryo just above the cotyledon(s).
  • Entire: Entire is a leaf margin without teeth lobes or divisions; smooth-edged.
  • Endosperm: Endosperm is the seed portion containing food reserves.
  • Endocarp: Endocarp is the inner layer of the pericarp (fruit wall).
  • Endemic: Endemic is a plant having a restricted area of distribution.
  • Emersed: Emersed is a term meaning above water.
  • Embryo: Embryo is the seed portion that develops into a juvenile plant.
  • Elongate: Elongate is a term meaning narrow and long.
  • Elliptic: Elliptic is a narrow shape with relatively rounded ends that is widest at the middle.
  • Ecotype: Ecotype is a strain or selection within a given species adapted to a particular environment.
F
  • Fusiform: Fusiform is a spindle shaped; long and narrowly elliptical with pointed ends.
  • Funnelform Funnel-Shaped: Funnelform Funnel-Shaped are terms meaning gradually widening outward.
  • Fruit: Fruit is a a matured ovary with its enclosed seeds; a ripened pistil.
  • Frond: Frond is a leaf of a fern including the stipe and blade.
  • Free: Free is a term meaning not fused or joined to any other organ.
  • Form: Form is a term meaning distinguishing stable taxonomic step below variety differing slightly often by a single characteristic.
  • Folded: Folded is the arrangement of the youngest leaf in the bud shoot where leaf buds are folded together lengthwise with the upper surface inside the fold.
  • Floret: Floret is a small flower of a dense cluster.
  • Flaccid: Flaccid is a term meaning without rigidity; limp or weak.
  • Flabellate: Flabellate is a term meaning fan-shaped.
  • First Leaf: First leaf is the subsequent leaf produced after the cotyledons in seedlings.
  • Filiform: Filiform is a term meaning thread-like long and very slender.
  • Filament: Filament is a anther-bearing stalk of a stamen (male part) of a flower; thread.
  • Fibrous Roots: Fibrous Roots are slender branched roots of similar size arising from a similar point.
  • Fascicle: Fascicle is a term meaning a bunch or cluster.
  • Family: Family is a taxonomic group between order and genus in rank which contains 1 or more genera.
G
  • Gynophore: Gynophore is a stalk on which an ovary is borne.
  • Gymnosperm: Gymnosperm is a plant that produces seeds but not fruits. The seeds are not borne within an ovary and are said to be naked hence the name.
  • Grass-Like: Grass-Like are leaves long and narrow usually more than 10 times as long as broad.
  • Glume: Glume is one of the pair of bracts at the base of a grass spikelet.
  • Globose: Globose is a term meaning shaped like a globe round.
  • Glaucous: Glaucous is a term meaning covered with a waxy coating appearing as whitish to blue-green in color.
  • Glandular Hair: Glandular hair is a a small hair terminated in a small pin head-like gland frequently secreting resin wax or other substances.
  • Gland: Gland is the secretory structure often a protuberance.
  • Glabrous: Glabrous is a term meaning smooth without hairs or bristles.
  • Genus (plural: Genera): Genus is a group of related species.
  • Genotype: Genotype is the hereditary makeup of a plant (or variety) which determines its inheritance.
H
  • Hypocotyl: Hypocotyl is the stem part below the cotyledons of a seedling.
  • Hybrid: Hybrid is a term meaning a cross between two species.
  • Hyaline: Hyaline is a term meaning transparent.
  • Herbaceous (herb): Herbaceous is a nonwoody plant that may die back to the ground in winter.
  • Head: Head is a dense cluster of stalkless flowers as in dandelion.
  • Hastate: Hastate is a term meaning arrowhead shape with pointed basal lobes.
  • Hammock: Hammock is a raised island of vegetation in a swamp or more commonly a temperate hardwood forest.
  • Halophyte: Halophyte is a plant that grows in salty soil.
  • Habitat: Habitat is the natural environment where a plant grows.
  • Habit: Habit is a term meaning the growth form of the plant.
I
  • Irregular Flower: Irregular flower is a term meaing having only one plane of symmetry or bilaterally symmetrical; usually having petals of varying size and shape.
  • Involute: Involute is a term meaning rolled inward.
  • Internode: Internode is the section of stem between two successive nodes or joints.
  • Intercalary Meristem: Intercalary meristem is the meristematic area between two previously differentiated tissues of certain organs such as between the leaf blade and sheath or between a node and internode that accounts for stem elongation in grasses.
  • Inflorescence: Inflorescence is the flowering portion of a plant.
  • Inferior: Inferior is a term meaning beneath.
  • Inferior Ovary: Inferior ovary is an ovary below the point of attachment of sepals and petals; the rest of the flower sits on the ovary.
  • Indeterminate: Indeterminate is a term meaning conditions where growth and differentiation are not stopped continuous.
  • Indehiscent: Indehiscent is a term meaning not splitting.
  • Imperfect Flower: Imperfect Flower are flowers lacking either male or female parts; unisexual flowers.
  • Immersed: Immersed is a term meaning growing under water; submerged.
J
  • Joint: Joint is a node of a grass stem.
K
  • Keel: Keel is a prominent ridge often comprised of tissue on both sides of a midrib of a glume or leaf blade for example which has grown together.
L
  • Long-Day Plants: Long-day plants are plants which initiate flowering under long day (short night) regimes.
  • Lodicule: Lodicule is one of two or three scales at the bottom of the ovary in many grasses.
  • Lobe: Lobe is a segment of a simple leaf notched rather deeply into curved or angular segments.
  • Linear: Linear is a long and narrow shape with parallel margins.
  • Ligule: Ligule is the projection at the inside junction of the grass leaf blade and collar which may be membrane-like or a row of hairs.
  • Lianous: Lianous is a climbing herbaceous or woody vine that roots in the ground.
  • Lemma: Lemma is the lowermost of the two bracts enclosing a grass flower.
  • Legume: Legume is a member of the pea or bean family having dry fruit (pod) that splits open along two longitudinal sutures.
  • Leaflet: Leaflet is one of the divisions of a compound leaf.
  • Leaf Bud: Leaf bud is a small axillary or terminal bud containing rudimentary foliage.
  • Leaf Axil: Leaf axil is a position on a stem between the leaf and the stem.
  • Lateral Shoot: Lateral shoot is a shoot originating from vegetative buds in the axil of leaves or from the nodes of stems rhizomes or stolons.
  • Lateral Bud: Lateral bud is a bud originating in the leaf axil on the side of the stem.
  • Lanceolate: Lanceolate is a shape longer than wide broadest below the middle; lance-shaped.
  • Lamina: Lamina is the extended flattened portion of a leaf or petal.
  • Labellum: Labellum is the lip-like portion of the perianth of an orchid flower.
M
  • Monoecious: Monoecious: are staminate (male) and the pistillate (female) flowers being in separate inflorescences but occurring on the same plant. Example: corn.
  • Monocotyledon Monocot: Monocotyledon or monocot are grass and grass-like plants in which embryos (seedlings) have one cotyledon (seed leaf) and mostly parallel-veined leaves inconspicuous flowers flower parts in multiples of 3's and no secondary growth.
  • Midvein: Midvein is the primary vein especially when keeled (or thickened).
  • Midrib: Midrib is the main or central vein or rib of a leaf or leaflet.
  • Mesocotyl: Mesocotyl is that portion of the grass seedling separating sheath and cotyledon.
  • Mesocarp: Mesocarp is the middle layer of the pericarp (or fruit wall).
  • Meristem: Meristem is tissue capable of dividing into various organs or parts.
  • Membranous: Membranous is a term meaning thin transparent and flexible: membrane-like.
  • Marsh: Marsh is wet or periodically inundated land typically treeless and composed of grasses cat-tails or other monocots.
  • Maritime: Maritime is a term meaning confined to the sea or sea coast.
  • Margin: Margin is the edge or border usually of a leaf.
  • Male: Male in flowers means having stamens but no pistils.
N
  • Nut: Nut is an indehiscent one-celled and one-seeded hard and bony fruit. Example: acorn.
  • Node: Node is a portion of a stem at which one or more leaves and roots are attached.
  • Nodding: Nodding is a term meaning hanging down.
  • Net-Veined: Net-veined is a term meaning with a network of veins; not parallel-veined.
  • Naturalized: Naturalized means introduced but self-seeding and surviving without human assistance.
  • Native: Native is a term meaning indigenous inhabitant; original.
O
  • Ovule: Ovule is the portion of the ovary of the flower which becomes the seed.
  • Ovoid: Ovoid is a term meaning egg-shaped.
  • Ovate: Ovate is a term meaning egg-shaped in outline; broadest below the middle.
  • Ovary: Ovary is the lower part of the pistil containing the ovules or later the seed.
  • Oval: Oval is a term meaning broadly elliptic.
  • Oval or Ovate: Oval is a shape similar to a hen's egg; widest below the middle.
  • Orbicular: Orbicular is a term meaning circular or nearly round.
  • Opposite: Opposite is an arrangement of paired leaves attached opposite each other at the same node.
  • Open: Open is a term meaning loose.
  • Opaque: Opaque means dull not transparent.
  • Odd-Pinnate: Odd-pinnate is a compound leaf with paired leaflets on opposite sides of the axis with an unpaired leaflet at the tip.
  • Ocrea (Ochrea): Ocrea is a sheath or tube around the stem at a node formed by a fusion of two stipules; common in the Polygonaceae.
  • Obtuse: Obtuse is the blunt or rounded at the end instead of being angular.
  • Obovate: Obovate is the inverted oval- or egg-shaped; widest above the middle.
  • Oblong: Oblong is an elongate shape with approximately parallel sides more or less rectangular; longer than wide.
  • Oblique: Oblique is a shape having sides of unequal length or form.
  • Oblanceolate: Oblanceolate is the opposite of lanceolate the terminal half the widest and tapering to the base.
P
  • Pyriform: Pyriform is a term meaning pear-shaped.
  • Punctate: Punctate is a term meaning with translucent or colored dots depressions or pits.
  • Pubescent: Pubescent is a term meaning covered with hairs.
  • Prostrate: Prostrate is a term meaning parallel to or lying flat on the ground.
  • Plumose: Plumose is a term meaning feathered or having fine hairs on each side.
  • Pith: Pith is the central soft tissue of a stem.
  • Pistillate: Pistillate are flowers bearing pistils but no stamens.
  • Pistil: Pistil is a female flower composed of stigma style and ovary and formed from one or more carpels.
  • Pinnatifid: Pinnatifid are pinnately lobed with lobes not quite reaching to midrib (somewhat resembling a feather).
  • Pinnately compound: Pinnately compound is a compound leaf with the leaflets arranged along a central common axis.
  • Pinnate: Pinnate is a type of compound leaf with the leaflets arranged on either side of a central axis.
  • Pinnate Venation: Pinnate venation is venation resembling a feather with veins branching from the main vein.
  • Pilose: Pilose is a term meaning hairy or the hairs being elongated slender and soft.
  • Petiole: Petiole is the stalk or stem of a leaf.
  • Petal: Petal is the inner floral leaf that makes up a flower?s corolla generally colored or white.
  • Pericarp: Pericarp is the wall of a matured ovary when it becomes a fruit.
  • Perianth: Perianth is the collective name for the two whorls of modified leaves (sepals and petals) which surround sex organs in the flower.
  • Perfect Flower: Perfect flower is a flower with both functional pistils (female) and stamens (male); bisexual.
  • Perennial: Perennial is a plant that normally lives for more than two years.
  • Peltate: Peltate is a type of leaf attachment where the stalk is attached inside the leaf margin.
  • Peduncle: Peduncle is a stalk or stem of a flower cluster or individual flower.
  • Pedicel: Pedicel is a stalk of a simple flower or spikelet.
  • Pectinate: Pectinate is a term meaning comb-like.
  • Parallel-Veined: Parallel-veined are the main and subsidiary veins running lengthwise as in the leaves of grasses.
  • Pappus: Pappus is a modified calyx of Asteraceae consisting of awns scales or bristles at the top of the achene.
  • Papillose: Papillose is a term meaning bearing nipple-shaped projections.
  • Papilla: Papilla is a minute nipple-shaped projection.
  • Panicle: Panicle is an inflorescence composed of several branches and sub-branches.
  • Palmately Compound: Palmately compound is a type of leaf arrangement where leaflets arise from a common point of attachment and spread outwards.
  • Palmate: Palmate is a type of leaf where leaflets or lobes originate from a common point and diverge like the fingers from the palm of the hand.
  • Palmate Venation: Palmate venation are three or more nearly equal veins extending out from the petiole like the fingers from the palm of the hand.
  • Palea: Palea is the uppermost (inner) of the two bracts enclosing the flower of a grass floret.
  • Paddle-Like: Paddle-like is a term meaning resembling the blade on an oar.
Q
  • Q: No terms could be found.
R
  • Runner: Runner is a slender stolon (or horizontal stem).
  • Rudimentary: Rudimentary is a term meaning small often incompletely developed.
  • Rosette: Rosette is a circular cluster of leaves usually appressed or located near the ground level.
  • Rolled: Rolled is a grass leaf bud that is cylindrical in arrangement applies to the youngest leaf in the bud shoot.
  • Rhombic: Rhombic is more or less diamond-shaped having straight margins and being widest in the middle.
  • Rhizome: Rhizome is a creeping horizontal underground stem producing shoots above ground and roots below; distinguished from a root by the presence of nodes buds or scale-like leaves; may originate from the main stem or from tillers.
  • Reticulate: Reticulate is a a network pattern netted.
  • Reniform: Reniform is a term meaning kidney- or bean-shaped.
  • Reflexed: Reflexed is a term meaning turned abruptly downward or backward.
  • Recurved: Recurved is a term meaning curved downward or backward.
  • Reclining: Reclining is a term meaning sprawling or lying down.
  • Receptacle: Receptacle is the swollen tip of the flower stalk to which flower parts are attached.
  • Ray Flower: Ray flower is a type of flower with a strap-shaped petal located around the margin of the flowering head found in many members of the Asteraceae (Compositae) family.
  • Radicle: Radicle is the embryo portion which grows into the primary root of the seedling.
  • Radiate: Radiate can be found in a plane from a common center like the spokes of a wheel.
  • Rachis: Rachis is the main stem or axis bearing flowers or compound (pinnate) leaves.
  • Rachilla: Rachilla is a small rachis like the central floral axis of a grass spikelet.
  • Raceme: Raceme is an elongated inflorescence with each flower on an individual stalk.
S
  • Symmetrical: Symmetrical means possessing one or more planes of symmetry; planes which divide the object into mirror-image halves.
  • Swale: Swale is the moist meadow area lower than the surrounding area.
  • Superior ovary: Superior ovary is a ovary sitting above and within the whorls of stamens petals and sepals.
  • Summer annual: Summer annual is a plant that germinates in spring grows and flowers in summer and sets seed in fall after which it dies.
  • Sucker: Sucker is a plant shoot that arises from an adventitious bud on a root.
  • Succulent: Succulent is a term meaning soft and fleshy.
  • Subulate: Subulate is a term meaning awl-shaped.
  • Subtended: Subtended is a term meaning underneath directly below or close to.
  • Subspecies (ssp): Subspecies are a form of a recognized species differing in one or more significant ways.
  • Style: Style is a term meaning more or less elongated part of the pistil (stalk) between the ovary and stigma.
  • Stolon: Stolon is a creeping above-ground stem that roots at the nodes.
  • Stipule (stipel): Stipule are bract-like appendages at the base of some leaves; foliaceous to glandlike.
  • Stigma: Stigma is the upper feathery part of the female flower pistil that receives pollen.
  • Sterile: Sterile is a term meaning without a functioning sex organ.
  • Stem: Stem is a plant organ for support leaf production food storage and limited food production
  • Stellate: Stellate is a term meaing star-shaped.
  • Staminode: Staminode is a non-functional or sterile stamen.
  • Stamen: Stamen is a male or pollen-bearing organ of a flowering plant consisting of the filament (stalk) and the anther.
  • Stalk: Stalk is any slender supporting structure such as a petiole for a leaf a peduncle for an inflorescence or a pedicel for a flower.
  • Spur: Spur is a tubular projection from a petal or sepal.
  • Spikelet: Spikelet is the basic individual unit of the spike of grasses and some sedges; composed of one or more flowers and their subtending bracts.
  • Spike: Spike is an unbranched inflorescence with the flowers sessil (stalkless) on a rachis.
  • Species: Species is a group of individuals having certain distinctive characteristics in common.
  • Spatulate: Spatulate is a shape broadest and rounded at the tip spoon- or spatula-shaped.
  • Spathe: Spathe is a large usually conspicuous often colored bract resembling a leaf or petal beneath or enclosing an inflorescence.
  • Solitary: Solitary is another term for alone.
  • Smooth: Smooth is a term meaning lacking hairs divisions or teeth; not rough to the touch.
  • Slough: Slough is a wet place usually shallow with stagnant or sluggish flow.
  • Sinuate: Sinuate is a type of leaf margin that is wavy with regularly spaced bends.
  • Simple: Simple is a type of leaf consisting of a blade not divided into individual leaflets; unbranched.
  • Sigmoid: Sigmoid is a term meaning S-shaped.
  • Shrub: Shrub is a woody perennial plant smaller than a tree often branched from the ground.
  • Short-Day Plants: Short-day plants are plants which initiate flowering best under short day (long night) regimes.
  • Shoot: Shoot is a general term for the aboveground portion of a plant.
  • Sheath: Sheath is the lower portion of a leaf which encircles the stem.
  • Seta: Seta (plural: setae) is a bristle.
  • Sessile: Sessile means without a petiole stem or stalk; usually refers to a leaf being attached directly on the axis or stem of a plant.
  • Serrate: Serrate: is a type of leaf margin with sharp teeth pointing forward; saw-toothed
  • Septate: Septate is a term meaning separated by walls.
  • Sepal: Sepal is the outer layer of a flower which is usually petal-like in appearance and green in color.
  • Seminal Root: Seminal root is a root arising from the base of the hypocotyl.
  • Seedhead: Seedhead is a collection of flowers clustered on a main stem; refers to the inflorescence of the grasses sedges and rushes.
  • Seed: Seed is a ripened ovule.
  • Secund: Secund is a term meaning arranged or turned to one side of the axis.
  • Scutellum: Scutellum is a a shield-shaped organ of grass embryos.
  • Scurfy: Scurfy is a term meaning covered with minute membranous scales.
  • Schizocarp: Schizocarp is a dry fruit splitting at maturity into dry one-seeded segments.
  • Scarious: Scarious is a term meaning thin membranous non-green and translucent.
  • Scale: Scale is any small thin dry membrane-like leaf or bract.
  • Scabrous: Scabrous is a term meaning rough to the touch with minute rough projections; sandpapery.
  • Savannah: Savannah is a grassy area with sparse trees.
  • Sagittate: Sagittate is a term meaning arrowhead-shaped.
T
  • Two-ranked: Two-ranked is described as coming off the stem in two different directions as in the grass family.
  • Turgid: Turgid is a swollen tissue from internal water pressure.
  • Tufted: Tufted is described as being in compact clusters forming clumps.
  • Tubular: Tubular is decribed as being cylindrical and hollow.
  • Tuber: Tuber is a thickened storage portion of a rhizome or stolon (stem) commonly its terminal end.
  • Truncate: Truncate is described as having a cut off square very blunt ending abruptly.
  • Trifoliate: Trifoliate is a type of compound leaf composed of three leaflets.
  • Trailing: Trailing means prostrate but not rooting.
  • Toothed: Toothed a saw projections (or ?teeth?) on the margins of leaves.
  • Tiller: Tiller a grass shoot usually erect originating intravaginally (grows upward within the enclosing leaf sheath) from axillary buds in the axis of a leaf or in the unelongated crown portion of a stem.
  • Three-ranked: Three-ranked means diverging from the stem in three directions as in the sedge family.
  • Terrestrial: Terrestrial means growing on land.
  • Terminal bud: Terminal bud is the bud located at the end or apex of a stem or branch.
  • Tendril: Tendril is a slender twisting thread-like structure that allows plants to climb; it may be part of a branch or a leaf.
  • Taxonomy: Taxonomy is the science of defining groups of biological organisms based on shared characteristics.
  • Taxonomic rank: Taxonomic rank is a level in a taxonomic hierarchy arrangement of life forms. In botany the gross taxonomic order involves: Family Subfamily Tribe Genus Species Subspecies Variety Form.
  • Taproot: Taproot is a single enlarged vertical main root lacking major divisions.
  • Tapering: Tapering maens gradually becoming smaller toward one end; not abrupt.
U
  • Unisexual: Unisexual means flowers having only male (staminate) or female (pistillate) elements.
  • Unilateral: Unilateral meaning one-sided or turned to one side.
  • Undulate: Undulate means with a wavy or irregular surface or margin (edge).
  • Umbel: Umbel is an inflorescence with pedicels arising from a common point of attachment.
  • Ubiquitous: Ubiquitous means occurring everywhere.
V
  • Verticillate: Verticillate means arranged in a whorl.
  • Vernation: Vernation is the arrangement of the youngest leaf in the bud shoot; either rolled or folded.
  • Vermiform: vermiform a term meaning worm-shaped.
  • Vein: Vein are ribs of a leaf; one of the vascular bundles of a leaf.
  • Variety (var): Variety is the distinguishing stable subdivision of a plant species differing in a minor trait such as leaf variegation.
  • Vaginate: Vaginate or otherwise known as sheathed.
W
  • Woody: Woody means consisting or composed of wood or wood-like tissue.
  • Winter annual: Winter annual is a plant that germinates in late summer grows vegetatively during winter flowers and sets seed in late spring to early summer after which it dies.
  • Winged: Winged means bearing one or more broad flanges along its length.
  • Whorled leaves: Whorled leaves are three or more leaves attached in a circular arrangement at the same node.
X
  • X: No terms could be found.
Y
  • Y: No terms could be found.
Z
  • Zygote: Zygote is a fertilized egg.