To gnaw is defined as to bite and wear away a small part at a time.(verb)
An example of to gnaw is a dog chewing on a bone.
See gnaw in Webster's New World College Dictionary
Origin: ME gnawen < OE gnagen, akin to Ger nagen (OHG gnagan) < IE *ghnēgh < base *ghen-, to gnaw away, rub away > gnash, gnat
See gnaw in American Heritage Dictionary 4
verb gnawed gnawed, gnaw·ing, gnaws verb, transitive
Origin: Middle English gnauen
Origin: , from Old English gnagan.
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