Online Etymology Dictionary

forebode (v.): "feel a secret premonition," especially of something evil, c. 1600, from fore- + bode. Transitive meaning "announce beforehand, presage," especially something undesirable, is from 1660s. Intransitive sense "to presage" is from 1711. Related: Foreboded; foreboding. Old English forebodian meant "to announce, declare."
foreboding (n.): late 14c., "a predilection, portent, omen," from fore- + verbal noun from bode. Meaning "sense of something bad about to happen" is from c. 1600. Old English equivalent form forebodung meant "prophecy." Related: Forebodingly.
forecast (v.): late 14c., "to scheme," from fore- "before" + casten in the sense of "contrive, plan, prepare" (late 14c.; see cast (v.)). Meaning "predict events" first attested late 15c. (cast (v.) "to perceive, notice" is from late 14c.). Related: Forecasting.
Whether we are to say forecast or forecasted in the past tense & participle depends on whether we regard the verb or the noun as the original from which the other is formed; ... The verb is in fact recorded 150 years earlier than the noun, & we may therefore thankfully rid ourselves of the ugly forecasted; it may be hoped that we should do so even if history were against us, but this time it is kind. [Fowler, 1926]
forecast (n.): early 15c., "forethought, prudence," probably from forecast (v.). Meaning "conjectured estimate of a future course" is from 1670s. A Middle English word for weather forecasting was aeromancy.
forecaster (n.): 1630s, agent noun from forecast (v.).
forecasting (n.): late 14c., verbal noun from forecast (v.).
forecastle (n.): c. 1400 (mid-14c. as Anglo-French forechasteil), "short raised deck in the fore part of the ship used in warfare," from Middle English fore- "before" + Anglo-French castel "fortified tower" (see castle (n.)). In broader reference to the part of a vessel forward of the fore rigging, late 15c.; hence, generally, "section of a ship where the sailors live" (by 1840). Spelling fo'c'sle reflects sailors' pronunciation.
foreclose (v.): late 13c., from Old French forclos, past participle of forclore "exclude, shut out; shun; drive away" (12c.), from fors "out" (Modern French hors; from Latin foris "outside;" see foreign) + clore "to shut" (see close (v.)). Senses in English influenced by words in for- (which is partly synonymous with the Latin word) and spelling by a mistaken association with native fore-. Specific mortgage law sense is first attested 1728. Other Middle English for- words in which the same prefix figures include forjuggen "condemn, convict, banish;" forloinen "forsake, stray from," and forfeit. Related: Foreclosed; foreclosing.
foreclosure (n.): 1728, from foreclose + -ure.
forefather (n.): "ancestor," c. 1300, from fore- + father (n.); perhaps modeled on or modified from Old Norse forfaðir. Similar formation in Dutch voorvader, German Vorvater, Danish forfædre (Old English had forð-fæder).
forefend (v.): see forfend.
forefinger (n.): mid-15c., from fore- + finger (n.). So called because it is considered the first next to the thumb. A Middle English name for it was lickpot (late 14c.).
forefront (n.): "front part," late 15c., a Germanic-Latin hybrid, from fore- + front (n.). Originally of buildings, later of battles. The main modern sense ("foremost place in some scene of action") is from the military meaning "front rank of an army" (1510s).
forego (v.): "to go before," Old English foregan "to go before," from fore- + go (v.). Related: Foregoer, foregoing; foregone. Similar formation in Dutch voorgaan, German vorgehen, Danish foregaa.

Phrase foregone conclusion echoes "Othello" [III.iii], but Shakespeare's sense was not necessarily the main modern one of "a decision already formed before the case is argued." Othello says it of Cassio's dream, and it is clear from the context that Othello means Cassio actually has been in bed with Desdemona before he allegedly dreamed it (the suspicion Iago is nourishing in him).
foregoing (adj.): mid-15c., "preceding, antecedent, going before in time or place," present participle adjective from forego. As a noun from 1660s.
foreground (n.): 1690s, "part of a landscape nearest the observer," from fore- + ground (n.). First used in English by Dryden ("Art of Painting"); compare Dutch voorgrond. Figurative use by 1816.
forehand (adj.): 1879 in reference to a tennis stroke; 1909 as a noun in this sense; from fore- + hand (n.). Earlier it meant "position in front or above" (1550s); hence forehanded "prudent, careful of the future" (1640s), which came to mean "well-provided, well-to-do," a sense which lingered in New England into 19c.
forehead (n.): Middle English forhed, from Old English forheafod "forehead, brow," from fore- + heafod (see head (n.)). Similar formation in Dutch voorhoofd, German Vorhaupt, Danish forhoved.
foreign (adj.): c. 1300, ferren, foran, foreyne, in reference to places, "outside the boundaries of a country;" of persons, "born in another country," from Old French forain "strange, foreign; outer, external, outdoor; remote, out-of-the-way" (12c.), from Medieval Latin foraneus "on the outside, exterior," from Latin foris (adv.) "outside," literally "out of doors," related to foris "a door," from PIE *dhwor-ans-, from root *dhwer- "door, doorway" (see door).

English spelling altered 17c., perhaps by influence of reign, sovereign. Sense of "alien to one's nature, not connected with, extraneous" attested late 14c. Meaning "pertaining to another country" (as in foreign policy) is from 1610s. Replaced native fremd. Related: Foreignness.
foreigner (n.): early 15c., foreyner; see foreign + -er (1).
In ordinary use chiefly applied to those who speak a foreign language as their native tongue; thus in England the term is not commonly understood to include Americans. [OED]
In American English from 1620s through mid-19c., however, it was used of a person from a different colony or state. Earlier as a noun in English was simple foreign (early 14c.), probably from Old French, which used the adjective as a noun meaning "foreigner;" also "outskirts; the outside world; latrine, privy." Spelling furriner, representing pronunciation, is from 1832, originally in Irish dialect pieces but by 1840s picked up by American dialect writers (Thomas Chandler Haliburton).
foreknowledge (n.): "prescience," 1530s, from fore- + knowledge. Earlier in this sense was foreknowing (late 14c.), from foreknow "have previous knowledge of, know beforehand." Old English had forewitan, Middle English forwiten "to foreknow."
foreleg (n.): late 15c., from fore- + leg (n.).
forelock (n.): "lock of hair growing above the forehead," Old English forelocca "forelock;" see fore- + lock (n.2).
"Opportunity has hair in front, behind she is bald; if you seize her by the forelock, you may hold her; but, if she once escapes, not Jupiter himself can catch her again." ["Dictionary of Latin Quotations, Proverbs, Maxims and Mottos," H.T. Riley, London, 1866]
foreman (n.): early 13c., "a leader," from fore- + man (n.). From 1530s as "principal juror;" 1570s in the sense of "principal workman." Similar formation in Dutch voorman, German Vormann, Danish formand. Also in 17c., a slang word for "penis." Fem. form forewoman is from 1709, originally of a jury; forelady is from 1867 in reference to juries, 1888 of shops, American English.
foremast (n.): also fore-mast, the first actual mast of a vessel, or the mast fore of the main-mast, 1580s, from fore- + mast (n.1).
foremost (adj.): Middle English formest, from Old English fyrmest, formest "earliest, first, most prominent," from Proto-Germanic *furmista-/*frumista- (related to Old English fruma "beginning"), from PIE *pre-mo-, suffixed (superlative) form of root *per- (1) "forward, through; before; first" (see per) + additional superlative suffix -est. For the -m-, see -most, and compare similarly formed Old Frisian formest, Gothic frumists. Altered on the assumption that it is a compound of fore and most. The same compound without the superlative -m- is first. Also in Old English as an adverb, "first of all, at first, in the first place."
forename (n.): 1530s, from fore- + name (n.). The equivalent of Latin praenomen. Old English had forenama. Middle English had fore-named in the sense "mentioned before" (c. 1200).
forenoon (n.): "the morning," especially the latter part of it, when business is done, c. 1500, from fore- + noon.
forensic (adj.): "pertaining to or suitable for courts of law," 1650s, with -ic + stem of Latin forensis "of a forum, place of assembly," related to forum "public place" (see forum). Later used especially in sense of "pertaining to legal trials," as in forensic medicine (1845). Related: Forensical (1580s).
forepart (n.): also fore-part, c. 1400, from fore- + part (n).
foreplay (n.): by 1921 in sexual sense, from fore- + play (n.); Freud's Vorlust was translated earlier as fore-pleasure (Brill, 1910). A more direct translation from the German would be thwarted by the sense drift in English lust (n.). Earlier as a theatrical term:
In fact the poem which Mr. Brooks has translated is but the "prologue to the swelling theme," the fore-play to the actual drama of Faust. ["The Christian Examiner and Religious Miscellany," Jan.-May 1857]
forerunner (n.): c. 1300, from fore- + runner. Middle English literal rendition of Latin praecursor, used in reference to John the Baptist as the forerunner of Christ. Old English had foreboda and forerynel.
foresee (v.): Old English foreseon "have a premonition," from fore- "before" + seon "to see, see ahead" (see see (v.)). Perhaps modeled on Latin providere. Related: Foresaw; foreseeing; foreseen. Similar formation in Dutch voorzien, German vorsehen.
foreseeable (adj.): 1804, from foresee + -able. Related: Foreseeably.
foreshadow (v.): "indicate beforehand," 1570s, figurative, from fore- + shadow (v.); the notion seems to be a shadow thrown before an advancing material object as an image of something suggestive of what is to come. Related: Foreshadowed; foreshadowing. As a noun from 1831. Old English had forescywa "shadow," forescywung "overshadowing."
foreshorten (v.): c. 1600, from fore- + shorten. Related: Foreshortened; foreshortening.
foresight (n.): also fore-sight, early 14c., "insight obtained beforehand;" also "prudence," from fore- + sight (n.). Perhaps modeled on Latin providentia. Compare German Vorsicht "attention, caution, cautiousness."
foreskin (n.): 1530s, from fore- + skin (n.). A loan-translation of Latin prepuce.
forest (n.): late 13c., "extensive tree-covered district," especially one set aside for royal hunting and under the protection of the king, from Old French forest "forest, wood, woodland" (Modern French forêt), probably ultimately from Late Latin/Medieval Latin forestem silvam "the outside woods," a term from the Capitularies of Charlemagne denoting "the royal forest." This word comes to Medieval Latin, perhaps via a Germanic source akin to Old High German forst, from Latin foris "outside" (see foreign). If so, the sense is "beyond the park," the park (Latin parcus; see park (n.)) being the main or central fenced woodland.

Another theory traces it through Medieval Latin forestis, originally "forest preserve, game preserve," from Latin forum in legal sense "court, judgment;" in other words "land subject to a ban" [Buck]. Replaced Old English wudu (see wood (n.)). Spanish and Portuguese floresta have been influenced by flor "flower."
forest (v.): "cover with trees or woods," 1818 (forested is attested from 1610s), from forest (n.).
forestall (v.): late 14c. (implied in forestalling), "to lie in wait for;" also "to intercept goods before they reach public markets and buy them privately," which formerly was a crime (mid-14c. in this sense in Anglo-French), from Old English noun foresteall "intervention, hindrance (of justice); an ambush, a waylaying," literally "a standing before (someone)," from fore- "before" + steall "standing position" (see stall (n.1)). Modern sense of "to anticipate and delay" is from 1580s. Related: Forestalled; forestalling.
forester (n.): late 13c. (late 12c. as a surname), "officer in charge of a forest," from Old French forestier "forest ranger, forest-dweller" (12c., also, as an adjective, "wild, rough, coarse, unsociable"), from forest (see forest (n.)).
forestry (n.): 1690s, "privilege of a royal forest," from forest (n.) + -ry or else from Old French foresterie, from forest (see forest (n.)). Meaning "science of managing forests" is from 1859.
foretaste (n.): early 15c., from fore- + taste (n.). As a verb, from mid-15c.
foretell (v.): "predict, prophesy," c. 1300, from fore- + tell (v.). Related: Foretold; foretelling.
forethought (n.): early 14c., "a thinking beforehand, the act of planning," verbal noun from forethink "think of something beforehand," from Old English foreþencan "to premeditate, consider;" see fore- + think. Meaning "prudence, provident care" is from 1719.
foretime (n.): "a previous time," 1530s, from fore- + time (n.). Related: Foretimes.
forever (adv.): late 14c., for ever; from for + ever. Often written as one word from late 17c. As a noun by 1858. Emphatic forevermore is from 1819.
forewarn (v.): early 14c., from fore- + warn. Related: Forewarned; forewarning.
foreword (n.): "introduction to a literary work," 1842, from fore- + word (n.); perhaps a loan-translation of German Vorwort "preface," modeled on Latin praefatio "preface."