mountain beaver
A rodent native to western North America (Aplodontia rufa); not a true beaver. The Japanese name is a direct translation of the English common name.
The mountain beaver is a rodent that lives in western North America.
Kanji spelling; usually written in kana.
Compound of 山 (yama, 'mountain') + ビーバー (bībā, 'beaver'), a calque of English 'mountain beaver'.