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A stout burrowing rodent (Aplodontia rufa) of the Pacific coast of North America, having small eyes and ears and feeding on vegetation such as ferns and tree seedlings. Also called sewellel.
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|Noun||1.||mountain beaver - bulky nocturnal burrowing rodent of uplands of the Pacific coast of North America; the most primitive living rodent|
gnawer, rodent - relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing