Source : Webster's Revised Unabridged Dictionary (1913)

Rhizopoda \Rhi*zop"o*da\, n. pl. [NL., fr. Gr. ??? a root +
   -poda.] (Zo["o]l.)
   An extensive class of Protozoa, including those which have
   pseudopodia, by means of which they move about and take their
   food. The principal groups are Lobosa (or Am[oe]bea),
   Helizoa, Radiolaria, and Foraminifera (or Reticularia). See
   {Protozoa}.

{Protozoa}, including {Infusoria} and {Rhizopoda}. For
definitions, see these names in the Vocabulary.

Source : WordNet®

Rhizopoda
     n : creeping protozoans: amoebas and foraminifers [syn: {subclass
         Rhizopoda}]