Source : Webster's Revised Unabridged Dictionary (1913)

Annelid \An`ne*lid\, Annelidan \An*nel"i*dan\, a. [F.
   ann['e]lide, fr. anneler to arrange in rings, OF. anel a
   ring, fr. L. anellus a ring, dim. of annulus a ring.]
   (Zo["o]l.)
   Of or pertaining to the Annelida. -- n. One of the Annelida.

Source : WordNet®

annelidan
     adj : relating to or belonging to or characteristic of any worms
           of the phylum Annelida [syn: {annelid}]