entomostraca

from WordNet (r) 3.0 (2006)

Entomostraca
    n 1: in some older classifications includes the Branchiopoda and
         Copepoda and Ostracoda and Cirripedia; no longer in
         technical use [syn: {Entomostraca}, {subclass
         Entomostraca}]

from The Collaborative International Dictionary of English v.0.48

Entomostraca \En`to*mos"tra*ca\, n. pl. [NL., fr. Gr. ? cut in
   pieces + ? burnt clay, the hard shell of Testacea.]
   (Zo["o]l.)
   One of the subclasses of Crustacea, including a large number
   of species, many of them minute. The group embraces several
   orders; as the {Phyllopoda}, {Ostracoda}, {Copepoda}, and
   {Pectostraca}. See {Copepoda}, {Phyllopoda}, and {Cladocera}.
   [1913 Webster]