ostracoda

from WordNet (r) 3.0 (2006)

Ostracoda
    n 1: seed shrimps [syn: {Ostracoda}, {subclass Ostracoda}]

from The Collaborative International Dictionary of English v.0.48

Ostracoda \Os*trac"o*da\, prop. n. pl. (Zool.)
   An order of Entomostraca possessing shrimplike bodies
   enclosed in hard bivalve shells; called also {seed shrimp}
   and {mussel shrimp}. They were formerly referred to as
   {Ostracoidea}. They are of small size, and swim freely about;
   many are less than 1 mm in length. Microfossils of certain
   extinct orders have been found extending back to the Cambrian
   age.
   [1913 Webster +PJC]

from The Collaborative International Dictionary of English v.0.48

Ostracoidea \Os`tra*coi"de*a\, n. pl. [NL., fr. Gr. 'o`strakon
   shell of a testacean + -oid.] (Zool.)
   An order of Entomostraca possessing hard bivalve shells. They
   are of small size, and swim freely about. Now usually written
   {Ostracoda}. [archaic]
   [1913 Webster +PJC]

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