des·man 
(dĕsmən)
(dĕsmən)n. pl. des·mans
Either of two aquatic, insectivorous, molelike mammals, Desmana moschata of eastern Europe and western Asia or Galemys pyrenaicus of southwest Europe, having dense brownish fur, a long snout, and a flattened scaly tail.
[Short for Swedish desmanråtta, muskrat : desman, musk (from Middle Low German desem, from Medieval Latin bisamum, of Semitic origin; see bśm in the Appendix of Semitic roots) + råtta, rat.]