What does this mean gnawed?

1a : to bite or chew on with the teeth especially : to wear away by persistent biting or nibbling a dog gnawing a bone. b : to make by gnawing rats gnawed a hole. 2a : to be a source of vexation to : plague anxiety always gnawing him. b : to affect like gnawing hunger gnawing her vitals. 3 : erode, corrode.

What does Gnarred mean?

v.i. gnarred, gnar•ring.

to snarl; growl.