gnaw

Gnaw is a verb meaning to bite, chew, or nibble persistently on something with teeth, causing wear or damage. It can also imply a persistent sensation, such as hunger, pain, or worry, that consumes attention. The act can be performed by animals or humans, and the object is often wood, bone, or other hard substances.

In biology, gnawing is characteristic of rodents and some lagomorphs, which have specialized dental anatomy. They possess continuously growing incisors that are worn down by gnawing against enamel on the opposite surfaces, creating sharp chisel edges. This adaptation supports feeding on tough plant materials and in some species, constructing nests or shelters.

In idiomatic use, phrases such as "gnaw at" describe something that troubles or preoccupies someone, as in a concern that gnaws at the mind. The verb also appears in expressions like "gnaw the bone," referring to the physical act of chewing meat from a bone. Synonyms include bite, chew, nibble, and chomp.

Etymology: The word is from Old English gnagan, related to Dutch knagen and German knagen; cognates appear in other Germanic languages. The related noun usage refers to the act or the sensation of gnawing, and the term has extended metaphorically in various phrasings.