\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.