an uninhibited spree or party; orgy: a wild debauch.
Origin: 1585–95; < Frenchdébaucher to entice away from duty, debauch, Old Frenchdesbauchier to disperse, scatter, equivalent to des-dis-1 + -bauchier, derivative of bauc, bauch beam (< Germanic; see balcony, balk; compare Frenchébaucher to rough-hew); hence, presumably, to hew (beams) > to split, separate > to separate from work or duty
1590s, from M.Fr. debaucher "entice from work or duty," from O.Fr. desbaucher "to lead astray," supposedly lit. "to trim (wood) to make a beam" (from bauch "beam," from Frankish balk; from the same Gmc. source that yielded English balk, q.v.). A sense of "shaving" something
away, perhaps, but the root is also said to be a word meaning "workshop," which gets toward the notion of "to lure someone off the job;" either way the sense evolution is unclear