v. t. [ imp. & p. p. Gnawed p. pr. & vb. n. Gnawing. ] [ OE. gnawen, AS. gnagan; akin to D. knagen, OHG. gnagan, nagan, G. nagen, Icel. & Sw. gnaga, Dan. gnave, nage. Cf. Nag to tease. ] 1. To bite, as something hard or tough, which is not readily separated or crushed; to bite off little by little, with effort; to wear or eat away by scraping or continuous biting with the teeth; to nibble at. [ 1913 Webster ]

His bones clean picked; his very bones they gnaw. Dryden. [ 1913 Webster ]

2. To bite in agony or rage. [ 1913 Webster ]

They gnawed their tongues for pain. Rev. xvi. 10. [ 1913 Webster ]

3. To corrode; to fret away; to waste. [ 1913 Webster ]

4. To trouble in a constant manner; to plague; to worry; to vex; -- usually used with at; as, his mounting debts gnawed at him. [ PJC ]

v. i. To use the teeth in biting; to bite with repeated effort, as in eating or removing with the teeth something hard, unwieldy, or unmanageable. [ 1913 Webster ]

I might well, like the spaniel, gnaw upon the chain that ties me. Sir P. Sidney. [ 1913 Webster ]

n. 1. One who, or that which, gnaws. [ 1913 Webster ]

2. (Zool.) A rodent. [ 1913 Webster ]