"put together clumsily or dishonestly," by 1771 (perhaps from 17c.); perhaps an alteration of fadge "make suit, fit" (1570s), a verb of unknown origin. The verb fudge later had an especial association with sailors and log books. The traditional story of the origin of the interjection fudge "lies! nonsense!" (1766; see fudge (n.2)) traces it to a sailor's retort to anything considered lies or nonsense, from Captain Fudge, "who always brought home his owners a good cargo of lies" [Isaac Disraeli, 1791, citing a pamphlet from 1700]. It seems there really was a late 17c. Captain Fudge, called "Lying Fudge," and perhaps his name reinforced this form of fadge in the sense of "contrive without the necessary materials." The surname is from Fuche, a pet form of the masc. proper name Fulcher, from Germanic and meaning literally "people-army."
type of confection, 1895, American English, apparently a word first used among students at women's colleges; perhaps a special use from fudge (v.) or its noun derivative, via the notion of "insubstantial" or of something "faked-up" on the spot. The verb was used in school slang, and compare fudge (n.) "a made-up story" (1797).
'He lies,' answered Lord Etherington, 'so far as he pretends I know of such papers. I consider the whole story as froth — foam, fudge, or whatever is most unsubstantial. ...' [Scott, "St. Ronan's Well," 1823]
"nonsense, rubbish," (1791), earlier and more usually as a contemptuous interjection, "lies! nonsense!" Probably a natural extension from fudge (v.) "put together clumsily or dishonestly," q.v. But Farmer suggests provincial French fuche, feuche, "an exclamation of contempt from Low German futsch = begone."