"one easily deceived or led astray by false representations," 1680s, from French dupe "deceived person," from duppe (early 15c.), thieves' jargon, perhaps from phrase de huppe "of the hoopoe," an extravagantly crested and reputedly stupid bird. For names of supposedly stupid birds applied to stupid persons, compare booby, goose (n.), gull (n.2) .
"to deceive, trick, mislead by imposing on one's credulity," 1704, from dupe (n.). Related: Duped; duping.
1690s, earlier cully (1660s) "a dupe, a sap-head," "a verdant fellow who is easily deceived, tricked, or imposed on" [Century Dictionary], rogues' slang, of uncertain origin.
Perhaps a shortening of cullion "base fellow," originally "testicle" (from French couillon, from Old French coillon "testicle; worthless fellow, dolt," from Latin coleus, literally "strainer bag;" see cojones). Another theory traces it to Romany (Gypsy) chulai "man." Also sometimes in the form cully, however some authorities assert cully was the canting term for "dupe" and cull was generic "man, fellow" without implication of gullibility. Compare also gullible. Related: Cullibility (1728).
"to beat up," 1818, originally "to strike the face" (in pugilism), from mug (n.2) "face." The general meaning "attack" is attested by 1846, and "attack to rob" by 1864. Perhaps influenced by thieves' slang mug "dupe, fool, sucker" (1851). Related: Mugged; mugging.
"fool, simpleton," 1855, of unknown origin, apparently from the surname and perhaps influenced by slang mug "dupe, fool" (1851; see mug (n.2)). It also was the name of simple card game (1855) and the word each player tried to call out before the other in the game when two cards matched. The name turns up frequently in humor magazines, "comic almanacks," etc. in 1840s and 1850s.