Middle English, from Old English onforan, contraction of prepositional phrase on foran "before in place, at the beginning of, in front of," from on (prep.), see a- (1), + foran (adv.) "in front," dative of for. In some cases probably it represents Old English ætforan "at-fore."

Attested from early 14c. as a preposition, "before in time," and as a conjunction, "earlier than the time when, before." Once the literary equivalent of before, it now has been replaced by that word except in nautical use, colloquial dialects, and in combinations such as aforesaid, aforethought.

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.

1550s, "be taken or regarded as," also "be in favor of," from go (v.) + for (adv.). Meaning "attack, assail" is from 1880. Go for broke is from 1951, American English colloquial.

c. 1200, from here + obsolete Old English toforan "formerly, before now," from to (prep.) + foran (adv.) "in front," dative of for. Also in Middle English heretoforn.

verbal phrase, attested by c. 1300 as "count for, be counted or considered as;" early 14c. as "be considered in lieu of;" late 14c. as "represent by way of sign." See stand (v.) + for (prep.). The sense of "put up with, tolerate" is attested from 1620s; modern use in this sense seems to be late 19c. U.S. colloquial.

"for this, for that, for it," Middle English variant spelling of therefore (q.v.); in modern use perhaps perceived as there + for.

Middle English ther-fore, from Old English þærfore; from there + fore, Old English and Middle English collateral form of for.

Since c. 1800, therefor has tended to be used in the sense of "for that, by reason of that," and therefore in the sense of "in consequence of that." Similar formation in Dutch daarvoor, German dafür, Danish derfor. Middle English also had a variant thereforn "for that reason" (mid-13c.).

1911 (originally in reference to cigars), from two for (a quarter); see two + for.

c. 1400, "not summoned," from un- (1) "not" + past participle of call (v.). Similar formation in Swedish okallad, Danish ukaldet. With for and sense of "unnecessary, intrusive" it is first attested 1610.

"for what cause or reason," c. 1200, hwarfore, from where (in the sense of "in which position or circumstances") + for (prep.). Similar formation in Dutch waarvoor, Old Norse hvar fyrir, Swedish varfor.