late 14c., "waste parts, refuse," especially the waste meat and entrails of a bird or animal used as food, from off (prep.) + fall (v.). The notion is "that which is allowed to 'fall off' the butcher's block as being of little use. Compare Middle Dutch afval, German abfall "waste, rubbish." Also compare English offcorn (mid-14c.) "refuse left after winnowing grain," offcast (late 14c.) "parts of plants normally uneaten." As verbs, Middle English had offhew, offhurl, offshred, offsmite.