GNAW

verb Etymology: Middle English ~en, from Old English gnagan; akin to Old High German gnagan to ~ Date: before 12th century transitive verb 1. to bite or chew on with the teeth, to make by ~ing , 2. to be a source of vexation to ; plague , to affect like ~ing , erode , corrode , intransitive verb to bite or nibble persistently , to produce an effect of or as if of ~ing , ~er noun