The Collaborative International Dictionary of English v.0.48:

Brachiopoda \Brach`i*op"o*da\, n. [NL., from Gr. ? arm + -poda.]
   (Zool.)
   A class of Molluscoidea having a symmetrical bivalve shell,
   often attached by a fleshy peduncle.
   [1913 Webster]

   Note: Within the shell is a pair of "arms," often long and
         spirally coiled, bearing rows of ciliated tentacles by
         which a current of water is made to flow into the
         mantle cavity, bringing the microscopic food to the
         mouth between the bases of the arms. The shell is both
         opened and closed by special muscles. They form two
         orders; Lyopoma, in which the shell is thin, and
         without a distinct hinge, as in Lingula; and
         Arthropoma, in which the firm calcareous shell has a
         regular hinge, as in Rhynchonella. See Arthropomata.
         [1913 Webster]

WordNet (r) 3.0 (2006):

Brachiopoda
    n 1: marine invertebrates that resemble mollusks [syn:
         Brachiopoda, phylum Brachiopoda]