Source : Webster's Revised Unabridged Dictionary (1913)

Cestoidea \Ces*toid"e*a\ (s[e^]s*toid"[-e]*[.a]), n. pl. [NL.,
   gr. Gr. kesto`s girdle + -oid.] (Zo["o]l.)
   A class of parasitic worms (Platelminthes) of which the
   tapeworms are the most common examples. The body is
   flattened, and usually but not always long, and composed of
   numerous joints or segments, each of which may contain a
   complete set of male and female reproductive organs. They
   have neither mouth nor intestine. See {Tapeworm}. [Written
   also {Cestoda}.]

Source : WordNet®

Cestoda
     n : tapeworms [syn: {class Cestoda}]