An example of a gnawing is a continuous pain in the elbow.
She stared at her feet, gnawing on her lower lip.
A rat, he declared, was gnawing at the pit of his stomach.
It is also fond of gnawing the bark of young trees, and thus often does great damage to plantations.
One thought had been gnawing at her consciousness since the first time she suspected him of being involved in drugs.
She stared at him, a gnawing feeling beginning in her stomach that had nothing to do with hunger.