1 a tr. (usu. foll. by away, off, in two, etc.) bite persistently; wear away by biting. b intr. (often foll. by at, into) bite, nibble.
2 a intr. (often foll. by at, into) (of a destructive agent, pain, fear, etc.) corrode; waste away; consume; torture. b tr. corrode, consume, torture, etc. with pain, fear, etc. (was gnawed by doubt).
3 tr. (as gnawing adj.) persistent; worrying.
Derivatives:
gnawingly adv.
Etymology: OE gnagen, ult. imit.
Useful english dictionary. 2012.