gnawing
v. B2 Upper Intermediate US //ˈnɔɪŋ// UK //nˈɔːɹɪŋ// gnaw·ing
v. to bite and chew something repeatedly, often because you are hungry or bored. It can also describe a feeling of worry or pain that keeps coming back.
v. to bite and chew repeatedly, typically on something hard or inedible; figuratively, to cause a persistent sense of worry or physical discomfort. Often used in the present participle form to describe a continuous, repetitive action.
The hungry mouse is gnawing on the wooden table leg.
He spent the entire flight gnawing on a stale pretzel while watching the same movie for the third time.
A gnawing sense of guilt began to take hold of him as he realized the full extent of the damage his carelessness had caused to the project.
From Middle English gnawynge; equivalent to gnaw + -ing.