GNAW (AT) is a verb that means to bite or chew on something persistently. The crossword solutions for this term are EAT and ERODE. EAT is a three-letter verb that means to consume food. ERODE is a five-letter verb that means to wear away gradually by natural processes such as wind or water. Together, these two words provide an accurate description of the action of gnawing, which is to bite or chew on something persistently until it is worn away.