From Old French (14th century), from Proto-Romance '*garg-' ("throat (imitative)").
Special words or expressions used by a particular profession or group that are difficult for others to understand; also, unintelligible talk or writing.
From Old French 'jargon' (twittering, chattering, speech not understood), of uncertain ultimate origin. One theory connects it to Gallo-Romance *gargone, from a base *garg- (throat), imitative of throaty sounds — the same root behind 'gargle,' 'gargoyle,' and 'gorge.' The earliest English uses meant 'meaningless chatter' or 'birdsong.' Chaucer used it to describe birds' twittering. The shift from 'unintelligible noise' to 'specialized professional vocabulary' happened gradually as outsiders perceived experts' technical talk as incomprehensible chattering. Key roots: *garg- (Proto-Romance: "throat (onomatopoeic)").