factyoudaoicibaDictYouDict[fact 词源字典]
fact: [16] A fact is literally ‘something that is done’. It comes from Latin factum ‘deed’, a noun based on the past participle of facere ‘do’. This verb, a distant relative of English do, has contributed richly to English vocabulary, from obvious derivatives like factitious [17] and factitive [19] to more heavily disguised forms such as difficult, effect, fashion, feasible, feature, and fetish, not to mention the -fic suffix of words like horrific and pacific, and the related verbal suffix -fy.

To begin with, English adopted the word in its original Latin sense ‘deed’, but this now survives only in legal contexts, such as ‘accessory after the fact’. There is sporadic evidence in classical Latin, however, of its use for ‘something that happens, event’, and this developed in post-classical times to produce ‘what actually is’, the word’s main modern sense in French fait and Italian fatto as well as in their English relative fact. Feat is essentially the same word as fact, filtered through Old French.
=> difficult, do, effect, fashion, feasible, feature, fetish[fact etymology, fact origin, 英语词源]
fact (n.)youdaoicibaDictYouDict
1530s, "action, anything done," especially "evil deed," from Latin factum "an event, occurrence, deed, achievement," in Medieval Latin also "state, condition, circumstance," literally "thing done" (source also of Old French fait, Spanish hecho, Italian fatto), noun use of neuter of factus, past participle of facere "to do" (see factitious). Main modern sense of "thing known to be true" is from 1630s, from notion of "something that has actually occurred."

Compare feat, which is an earlier adoption of the same word via French. Facts "real state of things (as distinguished from a statement of belief)" is from 1630s. In fact "in reality" is from 1707. Facts of life "harsh realities" is from 1854; euphemistic sense of "human sexual functions" first recorded 1913. Alliterative pairing of facts and figures is from 1727.
Facts and Figures are the most stubborn Evidences; they neither yield to the most persuasive Eloquence, nor bend to the most imperious Authority. [Abel Boyer, "The Political State of Great Britain," 1727]