ot·ter 
(
ŏt
ər)
n. pl. otter or
ot·ters 1. Any of various aquatic or semiaquatic carnivorous mammals of the mustelid subfamily Lutrinae, having webbed feet and dense, dark brown fur.
2. The fur of one of these animals.
[Middle English oter, from Old English otor; see wed-1 in the Appendix of Indo-European roots.]

otterAsian small-clawed otterAonyx cinerea