Source : Webster's Revised Unabridged Dictionary (1913)

Redia \Re"di*a\ (r?"d?*?), n.; pl. L. {Redi[ae]} (-[=e]), E.
   {Redias} (-?z). [NL.; of uncertain origin.] (Zo["o]l.)
   A kind of larva, or nurse, which is prroduced within the
   sporocyst of certain trematodes by asexual generation. It in
   turn produces, in the same way, either another generation of
   redi[ae], or else cercari[ae] within its own body. Called
   also {proscolex}, and {nurse}. See Illustration in Appendix.