fa·ba (fa´bə) n. broad bean; fava bean; horse bean. [< L faba bean]

fairy lantern n. any of a subset of species of the North American Calochortus Pursh (of the Liliaceae), which tend to generate flowers with enclosing globate petals, and to grow in closed forests; globe lily.

false ring n. a ring of secondary tissue growth which, as a result of environmental perturbations during the growing season, results in very small cells being produced and imitating the actual end of season growth.

fan·wort (fan´wôrt) n. any of a number of rooted aquatic herbs of the genus Cabomba Aubl. (of the Cabombaceae), apparently native to the Americas but now occurring elsewhere in slow or still waters, bearing submersed finely-divided leaves in pairs, and small flowers on apical pedicels raised above the water surface. [descriptive of the leaves]

far·ro (fär´ro) n. 1 emmer. 2 a food product prepared by boiling grains of einkorn, spelt, and/or emmer, so that they are more easily consumed but remain crunchy; grits. [< Ital. farro grande emmer < VL farrum < L far, farris a kind of wheat, grits]

fava bean n. broad bean; faba; horse bean. [< Ital. fava broad bean]

fa·vo·man·cy (fa´vō man´sē) n. a form of divination in which broad beans are tossed in the air, and their number and patterns upon the ground read to discern answers about the future. It was practiced by the Ubykh culture in Russia, as well as in Bosnia. [< L faba bean + Gk. manteía μαντεία divination] —fa´vo·man´cer, n.

fec·un·date (fek´ən dāt´) v.t. 1 to sexually fertilize. 2 to make prolific and fruitful. [< L fēcundēre to fertilize] —fec´un·da´tion, n. —fec·un´da·to´ry, adj.

feed·er (fē´dər) adj. n. —adj. 1 of a root or stem, being subsidiary to the taproot or to a major stem. 2 of a rootlet, serving to collect soil water. —n. any root or stem of this type.

fen·u·greek (fen´yə grēk´) n. an herbaceous plant (Trigonella foenum-graecum L., of the Fabaceae: Papilionoideae), native to eastern Europe, bearing white flowers and aromatic seeds often used as spice or in curry. [< OE fenogrecum < L fænugræcum Greek hay]

fer·ru·gi·nous (fã rü´ji nəs) adj. 1 of tissues, being of a reddish-brown or rusty colour. 2 of soil or other substrate, containing ferric oxides or rust. [< L ferrugino rust-coloured (< ferrum iron) + -ōsus prone to]

fer·tile (fėr´tīl´) adj. 1 of soil or land, able to produce vegetation or crops; possessing a suitable mixture of nutrients and physical features. 2 of an organism, capable of producing offspring. 3 of a seed or spore, capable of becoming a new individual. 4 of a zygote or seed, resulting from fertilization and capable of developing into sexual offspring. [ME < F < L fertilis fruitful, bearing in abundance] —fer·til´i·ty, n.

fer·ti·lise or fer·ti·lize (fėr´ti līz´) v.t. 1 render an ovum or one of two distinct isogametes fertile by placing its matching gamete adjacent. 2 in flowering plants, place pollen upon the stigma of a flower. 3 of land or water, make fertile by addition of nutrients and/or micelles. [ME fertile + -isen render, make (< OF -iser < LL -izāre < Gk. -izein -ιζειν)]

fer·ti·li·ser or fer·ti·li·zer (fėr´tə lī´zėr) n. 1 manure, and other similar combinations of organically useful compounds such as nitrates, phosphates, as well as mineral ions, which can be added to soil or water with the effect of increasing plant growth. 2 an organism or other agent which fertilises a plant. Insects are often fertilisers of flowers. [OF]

-fid (fid) comb.form., suffix. referring to the number or form of lobes comprising a body. May be preceded by a numerical or other adjectival prefix: pinnatifid. [< L fidus divided]

-field (fēld) comb.form., suffix. an area of land planted with a crop species, identified by the prefix. The suffix is usually appended without use of a dash or hyphen.

fig-apple n. an anomalous apple fruit, produced ca. 1807, from a tree which yielded no blossoms (or at least neither recognizable petals nor stamens), and whose fruit bore no core. [< F pome-figue]

fig-bean n. vernacular name for several species of Lupinus L. (of the Fabaceae: Papilionoideae); lupine.

fig-dust n. finely-ground oatmeal for feeding to birds.

fig-leaf n. 1 a leaf of the genus Ficus L. (of the Moraceae). 2 such a leaf depicted in art, frequently used as an artistic expedient for covering the pubes on sculptures and in paintings. 3 a disguise or defence.

fig-marigold n. vernacular name for several species of Mesembryanthemum L. (of the Aizoaceae), a succulent herb with showy flowers subject to opening only at specific times of day or night, and native to South Africa.

fil·i·form (fil´i fôrm´) adj. of leaves, and sometimes of other organs, appearing as a thread. [< L filum thread + forma shape]

fi·lo·sum (fī lō´süm) n. -sa. in ferns of suborder Hydropteridineae Rothwell & Stockey, a distinct layer to the outer megaspore exoperine, consisting of abundant fine hairs. [< L filum thread + -ōsum augmented, prone to]

fire lily n. the national flower of Zimbabwe (Gloriosa superba L., of the Colchicaceae), as well as a number of congeneric species, all native to Africa or India, and bearing showy flowers in the colours of flame; flame lily. The leaves of these species tend to bear apical tendrils, allowing their habitual climbing over other vegetation in open shrublands. The plants contain colchicine, which makes them toxic to livestock.

fis·sure (fish´ər) n. v.i. —n. an oblong opening, usually in bark, due to cracking or splitting. Fissures may have a distinctive form according to family or species of the related plant. —v.i. split or crack to form an oblong narrow opening. [ME < OF < L fissura < findere cleave] —fis´sured, adj.

five-faced bishop n. moschatel.

five-finger n. cinquefoil.

flac·cid (flak´sid) adj. of tissues or of individuals, drooping and inelastic due to lack of water. Antonym of turgid. [< F flaccide < L flaccidus < flaccus flabby] —flac·cid´i·ty, n. —flac´cid·ly, adv.

flail (flāl) n. v. —n. an implement used to thresh harvested grain, to dislodge the grains from stems and chaff; nunchuk. It often consists of a short rod attached at one end to a longer rod which is the handle. —v. 1 thresh grain with such an implement. 2 wave or swing wildly. [ME < OE fligel + OF flaiel < L flagellum whip]

flame·flow·er (flām´flou´ər) n. 1 any herb of the genus Kniphofia Moench (of the Asphodelaceae), largely native to Africa, and bearing spikes of tubular white, yellow, orange, or red flowers above a rosette of linear lanceolate leaves. 2 any herb of the genus Talinum Adans. (of the Portulacaceae), largely native to the Americas, and especially those bearing pink or red flowers. The taproot and leaves are of use as food and medicament. 3 any climbing shrub of the genus Pyrostegia C.Presl (of the Bignoniaceae), largely native to Brazil, and bearing a terminal cyme of bright red and orange flowers, and compound leaves with an apical tendril; trumpet flower.

flame lily n. fire lily.

fleece·flow·er (flēs´flou´ər) n. an ornamental perennial herb (Persicaria affinis (D.Don) Ronse Decr., of the Polygonaceae), related to the pinks, and similarly bearing pink flowers.

flex·u·ous (flek´shü əs) adj. of a stem or other axis, bearing distinct bends at intervals, zig-zag. [< L flexuosus prone to bend < flectere to bend] —flex´u·os´i·ty, n. —flex´u·ous·ly,  adv.

float (flōt) n. v.i. —n. in ferns of suborder Hydropteridineae Rothwell & Stockey, an approximately-spherical hollow pseudocellular appendage upon the outer surface of a macrospore, numbering three or four per spore, and enabling buoyancy. —v.i. 1 rest upon or near the surface of a liquid; remain buoyant. 2 be suspended freely within a body of gas or liquid. [< OE flotian < Gmc.]

Florin ring n. a subsidiary group of 4-8 small papillose cells which encircle each abaxial stoma in yew leaves. [< Carl Rudolf Florin (1894-1965), Swedish palæobotanist]

flow·er·er (flou´ə rėr) n. a plant which produces its flowers at a specified time or in a specified manner: nighttime flowerers.

flu·el·len (flü el´ən) n. 1 either of two creeping annuals (particularly Kickxia spuria (L.) Dumort. but also K. elatine (L.) Dumort., both of the Scrophulariaceae), native to southern Britain and adjacent territory in Europe, and bearing purple and yellow flowers. 2 Obs. any of several similar plants, especially Veronica officinalis L. (of the Scrophulariaceae), also creeping and bearing somewhat purple flowers. [< W Ilysiau Llewelyn Llewelyn’s flower]

flycatcher n. pitcher plant.

force (fôrs) v.t. induce a plant to develop or flower out of its normal season by artificial manipulation of temperature, humidity, and/or light. [ME < OF forcer < L forte strong, vigourous] —force´a·ble, adj.

forest island n. a stand or grove of forest species, very limited in area, founded upon ancient shell middens in seasonal flood plains of the Llanos de Moxos, in Bolivia. [< Sp. montículo boscoso]

-form (fôrm) comb.form., adjectival suffix. of the form or appearance indicated by the prefix (usually a plant growth form, or model genus). [< L forma appearance, shape]

four o’clock n. an herb (Mirabilis jalapa L., of the Nyctaginaceae), native to Peru but now much-cultivated, bearing opposite leaves and colourful flowers which actually show their colour in sepals, since they lack petals. Its flowers generally open in late day and remain open through the night.

fox·tail (foks´tāl´) n. any of several grasses belonging to the genera Alopecurus L., Ixophorus Schltdl., Paspalidium Stapf, and Setaria P.Beauv. (all of the Poaceae), and bearing inflorescences characterised as soft, light green, brushlike, and resembling the tail of a fox.

frame (frām) n. in horticulture, a boxlike translucent structure, often of glass, used to cover and protect plants. [< OE framian be of service]

frame bush n. in the novel Heretics of Dune by Frank Herbert, a jungle bush growing upon a planet of the Scattering, and which responds to direction by a human to grow by branching into the walls and roof of a secure dwelling. This takes about 5 years. The plant also bears hanging blue fruits at the distal ends of branches.

free·stone (frē´stōn´) adj. of certain drupes, possessing a stone from which the mesocarp is easily detached. Examples include certain peaches, particularly nectarines.

fringe-tree n. a shrub or small tree of southeastern North America (Chionanthus virginicus L., of the Oleaceae), whose inflorescences consist of a panicle of fragrant blossoms with narrow oblong white petals; old man’s beard.

frost ring n. a ring of early season secondary tissue growth which, as a result of a late ambient frost, stops cell growth and imitates an entire annual growth ring.

fruc·tal (frük´təl) adj. of or pertaining to fruit. [NL < L frūctus fruit + -ālis pertaining to or belonging to]

fruc·tar·i·an (frük´tãr´ē ən) n. adj. —n. fruitarian. —adj. of or pertaining to a fructarian diet. [on pattern of vegetarian] —fruc´tar´i·an·ism, n.

fruc·ted (frük´tid) adj. in heraldry, of an image of a plant of any kind which is represented as bearing fruit. [< L frūctus fruit + ME -ed adjectival suffix]

fruit·ar·i·an (frü´tãr´ē ən) n. adj. —n. one who, or that which, nourishes themself by a diet consisting largely of fruit; fructarian. —adj. of or pertaining to a fruitarian diet. [on pattern of vegetarian] —fruit´ar´i·an·ism, n.

fruit·er (frü´tėr) n. a tree or – more broadly – a plant which produces its fruit at a specified time or in a specified manner: wet-season fruiters.

fruit·er·er (früt´ər ėr) n. one who sells fruit; a fruit vendor. [ME]

frui·ting (frü´ting) n. 1 the time of achievement of fruit maturity. 2 ripening, in a general sense; infructescence.

frush (frush) adj. N.Country. said of wood apt to splinter and/or break.

-fu·gal (-fū´gəl) comb.form., adjectival suffix. tending to move away from or flee the causative factor defined by the prefix. [< L fugāre cause to flee]

-fuge (fūzh) comb.form., suffix. 1 a plant or taxon which tends to move away from or flee the causative factor defined by the prefix, but which benefits from exposure to its opposite. 2 of or pertaining to this growth preference. [< L fugio flee] —-fu´gous, adj.

fu·mi·to·ry (fū´mə tô´rē) n. any of the numerous species of the genus Fumaria L. (of the Papaveraceae), native to Europe and Africa, and bearing finely-divided greyish leaves. [ME < OF fumeterre < Med.L fumus terrae smoke of the earth]

fun·gi·stat·ic (fung´gi sta´tik) adj. inhibiting the growth of fungi. [< L fungus mushroom + NL staticus (< Gk. statikos στατικός standing)] —fun´gi·stat´i·cal·ly, adv.

fu·si·form (fū´zi fôrm´) adj. of a free-standing three-dimensional organ, or other object: widest in its central portion and tapering to either end, spindle-shaped. [< L fusus spindle + fōrma shape, appearance]