Word Unit: forbi-, forb- (Greek: phorbe, fodder, from pherbein, to graze; by extension: fodder, food; any herb other than grass, a broadleaf herb; a weed)
Word Unit: fore- (Old English: a prefix meaning before in place, rank, or time; in advance)
Word Unit: foren-, fore- (Latin: forensis of a forum, place of assembly; public, public speaking; foras, foranus, outside, residing outside, out of doors)
Word Unit: form-, -form, forma-, format- (Latin: shape, structure, figure, outer appearance, composition, to compose; visual appearance; spacial arrangement; to develop or to acquire; to produce)

Inter-related cross references, directly or indirectly, involving word units dealing with "form, shape, appearance": eido-; figur-; icono-; ideo-; imag-; morpho-; -oid; typo-.

Word Unit: formic-, form-, -formic (Latin: ant, ants)

Another word unit that is related directly to "ants": myrmeco-.

Word Unit: formid- (Latin: formido, "terror"; causing fear, terrible; to dread, to fear)
Word Unit: fornic-, fornix- (Latin: arch; vault)
Word Unit: fort-, forc- (Latin: brave; power, strength, strong)
Word Unit: fortu-, fortun- (Latin: chance, fate, luck)

A cross reference of other word family units that are related directly, or indirectly, to: "chance, luck, fate": aleato-; auspic-; cad-; -mancy; serendipity; sorc-; temer-; tycho-.

Word Unit: foss-, fossili-, fossil-, fossor- + (Latin: to dig, digging; dug out, dug up from beneath the surface; ditch, trench)
Word Unit: fove-, fovei- + (Latin: pit)
Word Unit: Fracking, Hydro Fracking, Hydraulic Fracturing Content Entries (Hydraulic fracturing, or fracking, is the practice of extracting natural gas from underground shale deposits by injecting high-pressure streams of water, sand, and chemicals)
Word Unit: frag-, frang-, fract-, fring- (Latin: break, breaking; broken; cracked)

Related break, broken-word units: clast-; rupt-.

Word Unit: frater-, frat- (Latin: brother, brotherly, brotherhood)
Word Unit: fren- + (Latin: rein, bridle, a bit (as in a horses mouth); by extension, a medical term for a connecting fold of membrane in the body)
Word Unit: frequen-, frequent- (Latin: crowded, numerous; repeated, repetition, constant)
Word Unit: friab- (Latin: crumble, fragile, broken into small pieces)
Word Unit: frica-, frict-, -frice + (Latin: a rubbing, to rub)

Cross references of word families that are related directly, or indirectly, to: "rub, rubbing; wear away; wipe": bruxo, brux-; terg-; tribo-; -tripsy; trit-.

Word Unit: frigo-, frig- (Latin: cold, frost; freezing)

Cross references of word families that are related directly or indirectly to "winter, freezing, frost, and/or cold": algid- (cold, chilly); cheimo-, chimo- (winter, cold); crymo-, krymo- (cold, chill, frost); cryo-, kryo-; (cold, freezing); gel-, gelati- (freeze, frost, congeal); hiber- (winter, wintry); pago- (cold, freezing); psychro- (cold); rhigo- (cold, frost; shiver).

Word Unit: front-, fronto- (Latin: forehead, brow, the forepart of anything; that which projects)