noun
: any of numerous marine crabs especially of the family Portunidae that have some of the joints of one or more pairs of legs flattened and fringed so as to serve as fins
noun
: any of numerous marine crabs especially of the family Portunidae that have some of the joints of one or more pairs of legs flattened and fringed so as to serve as fins
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012