transitive verb gnawed, gnawed or Raregnawn, gnawing gnaw′·ing

1. to cut, bite, and wear away bit by bit with the teeth
2. to make by gnawing to gnaw a hole
3. to consume; wear away; corrode
4. to torment, as by constant pain, fear, etc.; harass

Etymology: ME gnawen < OE gnagen, akin to Ger nagen (OHG gnagan) < IE *ghnēgh < base *ghen-, to gnaw away, rub away > gnash, gnat

intransitive verb

1. to bite repeatedly: with on, away, at, etc.
2. to produce a biting, consuming, corroding, eroding, tormenting, etc. effect: with on, at, etc. waves gnawed away at the shore; fear gnawed on his consciousness