Source : Webster's Revised Unabridged Dictionary (1913)

Amphipoda \Am*phip"o*da\, n. pl. [NL., FR. Gr. ? + ?, ? foot.]
   (Zo["o]l.)
   A numerous group of fourteen -- footed Crustacea, inhabiting
   both fresh and salt water. The body is usually compressed
   laterally, and the anterior pairs or legs are directed
   downward and forward, but the posterior legs are usually
   turned upward and backward. The beach flea is an example. See
   {Tetradecapoda} and {Arthrostraca}.

Source : WordNet®

Amphipoda
     n : small flat-bodied semi-terrestrial crustaceans: whale lice;
         sand-hoppers; skeleton shrimp [syn: {order Amphipoda}]