of unknown origin; attested in London criminal slang as adjective (1775, "counterfeit"), verb (1812, "to rob"), and noun (1851, "a swindle;" of persons 1888, "a swindler"), but probably older. A likely source is feague "to spruce up by artificial means," from German fegen "polish, sweep," also "to clear out, plunder" in colloquial use. "Much of our early thieves' slang is Ger. or Du., and dates from the Thirty Years' War" [Weekley]. Or it may be from Latin facere "to do." Century Dictionary notes that "thieves' slang is shifting and has no history."
The nautical word meaning "one of the windings of a cable or hawser in a coil" probably is unrelated, from Swedish veck "a fold." As a verb, "to feign, simulate" from 1941. To fake it is from 1915, jazz slang; to fake (someone) out is from 1940s, originally in sports. Related: Faked; fakes; faking.
The jazz musician's fake book is attested from 1951. Fake news "journalism that is deliberately misleading" is attested from 1894; popularized in the 2016 U.S. presidential campaign.
also felafel, popular Middle-Eastern food, by 1951 as a traveler's word, not common or domestic in English until 1970s; from Arabic falafil, said to mean "crunchy."
"hooked, curved like a scythe or sickle," 1801, from Latin falcatus "sickle-shaped, hooked, curved," from falcem (nominative falx) "sickle," which is of uncertain origin, perhaps a borrowing from a non-Latin Indo-European language of Italy. De Vaan lists cognates as Old Irish delg "thorn, pin," Welsh dala "sting," Lithuanian dilgė "nettle," Old Norse dalkr "pin, spine, dagger," Old English delg "clasp." Related: Falcated; falcation; falciform (1766).