Source : Webster's Revised Unabridged Dictionary (1913)

Rotifera \Ro*tif"e*ra\, n.; pl. [NL., from L. rota ? wheel +
   ferre to bear.] (Zo["o]l.)
   An order of minute worms which usually have one or two groups
   of vibrating cilia on the head, which, when in motion, often
   give an appearance of rapidly revolving wheels. The species
   are very numerous in fresh waters, and are very diversified
   in form and habits.

Source : WordNet®

Rotifera
     n : a phylum including: rotifers [syn: {phylum Rotifera}]