gnaw

Etymology

From Middle English gnawen, gnaȝen, from Old English gnagan, from Proto-Germanic *gnaganą. Cognate with Dutch knagen, German nagen, Norwegian Bokmål gnage, Norwegian Nynorsk gnaga, Swedish gnaga. Probably from Proto-Indo-European *gʰnēgʰ- (“to gnaw, scratch”).

verb

1. (transitive, intransitive) To bite something persistently, especially something tough.
   The dog gnawed the bone until it broke in two.
2. (intransitive) To produce excessive anxiety or worry.
   Her comment gnawed at me all day and I couldn't think about anything else.
3. To corrode; to fret away; to waste.

noun

1. the act of gnawing
   have a gnaw of a bone