Simple past tense and past participle of gnaw.(verb)
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Use "gnawed" in a sentence
"Coleridge, "With blood was it planted; it was rocked in tempests; the goat, the ass, and the stag gnawed it, the wild boar whetted its tusk upon its bark; the deep scars are still extant on its trunk, and the path of the lightning may be traced among its higher branches!""
"(Asked on NBC after the race if that streak had "gnawed" at him, Pletcher answered, "not as much as everybody else who made a big deal out of it" — but by then we'd been hooked on his saga.)"
"Bobby had tremendous emotional pull with the public, and that must have gnawed at Johnson, too."