Any carnivorous animal of the genus Lutra, and related genera. Several species are described. They have large, flattish heads, short ears, and webbed toes. They are aquatic, and feed on fish. Their fur is soft and valuable. The common otter of Europe is Lutra vulgaris; the American otter is L. Canadensis; other species inhabit South America and Asia.
- Any of various aquatic, carnivorous mammals of the genus Lutra and allied genera, related to the minks and weasels and having webbed feet and dense, dark brown fur.
- The fur of this mammal.