Debauch: 1595, 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 Frank. balk; from the same Gmc. source that yielded Eng. 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.