Muskrat \Musk"rat`\, n. 1. (Zo["o]l.) A North American aquatic fur-bearing rodent ({Fiber zibethicus}). It resembles a rat in color and having a long scaly tail, but the tail is compressed, the bind 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}, and {ondatra}.