Muskrat (?), n. 1. (Zoöl.) A North American aquatic fur-bearing rodent (Ondatra zibethica formerly Fiber zibethicus). It resembles a rat in color and having a long scaly tail, but the tail is compressed, the hind feet are webbed, and the ears are concealed in the fur. It has scent glands which secrete a substance having a strong odor of musk. Called also musquash, musk beaver, ondatra, and sometimes water rat.
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2. (Zoöl.) The musk shrew.
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3. (Zoöl.) The desman.
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