Online Etymology Dictionary

foreclose: late 13c., from O.Fr. forclos, pp. of forclore "exclude," from fors "out" (from L. foris "outside;" see foreign) + clore "to shut." Specific mortgage law sense is first attested 1728.
forefather: "ancestor," c.1300, from fore + father; perhaps directly from O.N. forfaðir.
forefront: c.1470, a Gmc.-L. hybrid, from fore + front. Originally of buildings; the main modern sense is from military meaning "front rank of an army" (1513).
forego: O.E. forgan "go away, pass over, leave undone," from for- "away" + gan "go." Usually in foregone conclusion, which was popularized in Shakespeare's "Othello" [III.iii], but his sense was not necessarily the main modern one of "a decision already formed before the case is argued." The similar foredone is now archaic, replaced by done for.
foreground: 1695, from fore + ground. First used in Eng. by Dryden, originally in painting (cf. Du. voorgrond).
forehand: tennis stroke, 1889, from fore + hand.
forehead: O.E. forheafod, from for(e)- + heafod (see head).
foreign: c.1300, ferren, foreyne "out of doors," from O.Fr. forain, from L.L. foranus "on the outside, exterior," from L. foris "outside," lit. "out of doors," related to fores "door;" spelling altered 17c. perhaps by influence of reign, sovereign. Replaced native fremd. Sense of "not in one's own land" is first attested late 14c.
foreman: 1530s in the sense of "principal juror;" 1570s in the sense of "principal workman;" from fore + man. Earliest attested meaning (early 15c.) was "a leader."
foremost: O.E. fyrmest "earliest, first, most prominent," from P.Gmc. *formo- (related to O.E. fruma "beginning"), superl. of the root of Eng. fore + additional superl. suffix -est. Cf. O.Fris. formest, Goth. frumists. Altered on the assumption that it is a compound of fore and most.
forensic: 1581, from L. forensis "of a forum, place of assembly," from forum. Used in sense of "pertaining to legal trials," as in forensic medicine (1845).
foreplay: in sexual sense, by 1911, from fore + play. Earlier as a theatrical term (late 19c.).
forerunner: c.1300, from fore + runner. M.E. rendition of L. præcursor, in reference to John the Baptist as the forerunner of Christ.
foresee: O.E. forseon "have a premonition," from fore- "before" + seon "to see, see ahead." Foresight is from c.1300.
foreshadow: 1570s, from fore + shadow; the notion is of a shadow thrown before an advancing material object as an image of something suggestive of what is to come. Related: Foreshadowing.
foreshorten: c.1600, from fore + shorten.
foreskin: 1535, from fore + skin. A loan-translation of L. prepuce.
forest: c.1300, "extensive tree-covered district," especially one set aside for royal hunting and under the protection of the king, from O.Fr. forest, probably from L.L./M.L. forestem silvam "the outside woods," a term from the Capitularies of Charlemagne denoting "the royal forest;" perhaps via O.H.G. forst, from L. foris "outside," with a sense of "beyond the park," the park being the main or central fenced woodland. Another theory traces it through M.L. forestis, originally "forest preserve, game preserve," from L. forum in legal sense "court, judgment;" in other words "land subject to a ban." Replaced O.E. wudu.
forestall: O.E. foresteall "an ambush, a waylaying," from fore "before" + steall "standing position" (see stall (1)). Modern sense of "to anticipate and delay" is from 1585.
foretell: c.1300, from fore + tell.
forethought: c.1300, from fore + thought.
forever (adv.): 1660s, from fore + ever.
foreword: 1842, perhaps a loan-translation of Ger. Vorwart "preface," modeled on L. præfatio "preface."
forfeit (n.): c.1300, from O.Fr. forfait "crime," originally pp. of forfaire "transgress," from for- "outside, beyond," + faire "to do" (from L. facere; see factitious). Translating M.L. foris factum. Sense shifted c.1450 from the crime to the penalty.
forfend: 1382, "to protect, prohibit," a hybrid from for- + fend, from L. defendere "to ward off."
forge (n.): 1279, from O.Fr. forge, earlier faverge, from L. fabrica "workshop," from faber (gen. fabri) "workman in hard materials, smith." Sense of "to counterfeit" is in Anglo-Fr. verb forger "falsify," from O.Fr. forgier, from L. fabricari "to frame, construct, build." Forgery is first recorded 1574.
forge (v.): 1611, "make way, move ahead," most likely an alteration of force, but perhaps from forge (n.), via notion of steady hammering at something. Originally nautical, in referrence to vessels.
forget: O.E. forgytan, from for- "passing by, letting go" (cf. forbear, forgo) + gietan "to grasp" (see get). A common Gmc. construction (cf. O.S. fargetan, Du. vergeten, Ger. vergessen "to forget"). The literal sense would be "to lose (one's) grip on," but that is not recorded in any Gmc. language. Forgettable (1845) first attested in Carlyle. Forget-me-not (the flowering plant Myosotis palustris) is so called from 1532, from O.Fr. ne m'oubliez mye; in 15c. the flower was supposed to ensure that those wearing it should never be forgotten by their lovers. Similar loan-transl. into other languages, cf. Ger. Vergißmeinnicht, Sw. forgätmigej, Hungarian nefelejcs, Czech nezabudka.
forgive: O.E. forgiefan "give, grant, allow," also "to give up" and "to give in marriage;" from for- "completely" + giefan "give" (see give). The modern sense of "to give up desire or power to punish" is from use of the compound as a Gmc. loan-translation of L. perdonare (cf. Du. vergeven, Ger. vergeben; see pardon).
forgo: see forego.
fork: O.E. forca "forked instrument used by torturers," from L. furca "pitchfork," of uncertain origin. Table forks were not generally used in England until 15c. The word is first attested in this sense in Eng. in a will of 1463, probably from O.N.Fr. forque, from the L. word. The verb "to divide in branches" is from the noun. Fork-lift (truck) first attested 1946. The slang verb phrase fork up (or out) "give over" is from 1831.
forlorn: 1154, "depraved," pp. of obsolete forlesan "be deprived of, lose, abandon," from O.E. forleosan, from for- "completely" + leosan "to lose" (see lose). In the Mercian hymns, L. perditionis is glossed by O.E. forlorenisse. Originally "forsaken, abandoned;" sense of "wretched, miserable" first recorded 1582. Commonly in forlorn hope (1579), which is a partial translation of Du. verloren hoop, in which hoop means "troop, band," lit. "heap," and the sense of the whole phrase is of a suicide mission. The phrase is usually used incorrectly in Eng., and the misuse has colored the sense of forlorn.
form: early 13c., from O.Fr. forme, from L. forma "form, mold, shape, case," origin unknown. One theory holds that it is from Gk. morphe "form, beauty, outward appearance" (see morphine) via Etruscan. Sense of "behavior" is first recorded late 14c. The verb is attested from c.1300.
formal: late 14c., from L. formalis, from forma (see form). Short for formal dance, first recorded 1946. Formality in the depreciative sense is from 1647. Formalism is from 1840 as "strict adherence to prescribed forms;" 1943 in ref. to Rus. literary movement (1916-30).
formaldehyde: 1872, formed from form(ic acid) + aldehyde, coined by Ger. chemist Justus von Liebig (1803-73), abbreviation of al(cohol) dehyd(rogenatum) "dehydrogenated alcohol."
format: 1840, via Fr. & Ger. from Mod.L. liber formatus "a book formed" (in such and such a way), referring to shape, size; from pp. of formare "to form." The verb, used chiefly of computers, is first attested 1964.
former: "earlier in time," c.1160, comparative of forme "first," patterned on formest "foremost" (see foremost). An unusual case of a comparative formed from a superlative (the -m- is a superlative element; the word was formed on the analogy of foremost).
formic acid: 1791, coined from L. formica "ant;" so called because it was obtained from red ants.
Formica: 1946, proprietary name (1922), from the original manufacturer, Formica Insulation Co. of Cincinnati, Ohio.
formidable: 1508, from M.Fr. formidable, from L. formidabilis, from formidare "to fear," from formido "terror, dread."
Formosa: old name of Taiwan, given by Portuguese, from Port. Formosa insula "beautiful island," from fem. of L. formosus "beautiful."
formula: 1638, from L. formula "form, rule, method, formula," lit. "small form," dim. of forma "form." Originally, "words used in a ceremony or ritual." Modern sense is colored by Carlyle's use of the word for "rule slavishly followed without understanding" (1837). Formulaic is from 1882; formulate is 1860.
"Men who try to speak what they believe, are naked men fighting men quilted sevenfold in formulae." [Charles Kingsley, "Letters," 1861]
fornication: c.1300, from O.Fr. fornication, from L.L. fornicationem (nom. fornicatio), from fornicari "fornicate," from L. fornix (gen. fornicis) "brothel," originally "arch, vaulted chamber" (Roman prostitutes commonly solicited from under the arches of certain buildings), from fornus "oven of arched or domed shape." Strictly, "voluntary sex between an unmarried man and an unmarried woman;" extended in the Bible to adultery.
forsake: O.E. forsacan "decline, refuse," from for- "completely" + sacan "to deny, refuse" (see sake).
forsooth: O.E. forsoð, from for-, intensive prefix, + soð "truth" (see sooth).
forswear: O.E. forswerian "swear falsely," also "abandon or renounce on oath," from for- "completely" + swerian "to swear."
forsythia: 1814, coined 1805 in Mod.L. in honor of William Forsyth (1737-1804), Scottish horticulturalist who brought the shrub from China.
fort: 1557, from M.Fr. fort, noun use of O.Fr. fort (adj.) "strong, fortified," from L. fortis "strong," from O.Latin forctus, from PIE base *bheregh- "high, elevated" (cf. Skt. brmhati "strengthens, elevates," O.H.G. berg "hill").
forte: 1648, from Fr. fort "strong point (of a sword blade)," also "fort," from M.Fr. fort (see fort); final -e- added 18c. in imitation of It. forte "strong." Meaning "strong point of a person" is from 1682.
forth: O.E. forðian "forward, onward," perf. of for(e), from P.Gmc. *furtha- (cf. O.N. forð, Du. voort, Ger. fort), from PIE *prto-, from the root of fore (q.v.). Forthright is O.E. forðriht; forthcoming "about to happen" is from 1521; forthwith "right away" is from c.1450.