The Collaborative International Dictionary of English v.0.48:

oligochaete \oligochaete\ n.
   Any of an order of hermaphroditic terrestrial and aquatic
   annelids (including the earthworms) having bristles borne
   singly along the length of the body; a member of the
   Oligochaeta.

   Syn: oligochaete worm.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

oligochaete
    n 1: hermaphroditic terrestrial and aquatic annelids having
         bristles borne singly along the length of the body [syn:
         oligochaete, oligochaete worm]