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n. 原牛（古代欧洲野牛，已灭绝）
复数：aurochs
Distinctions between aurochs and American bisons are not substantial.
欧洲野牛和美洲野牛的区别不明显。
The aurochs were ancient wild cattle.
野牛是古代的野生牛类。
n.[脊椎]欧洲野牛
wisent
bison
