uropod

U"ro*pod, n. Etym: [2d uro- + -pod.] (Zoöl.) Defn: Any one of the abdominal appendages of a crustacean, especially one of the posterior ones, which are often larger than the rest, and different in structure, and are used chiefly in locomotion. See Illust. of Crustacea, and Stomapoda.

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