Word Origin & History
attested in London criminal slang as adj. (1775), verb (1812), and noun (1827), but probably older. Likely source is feague "to spruce up by artificial means," from Ger. 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 L. facere "to do." Related: Faked; faker; fakes; faking.