Source : Webster's Revised Unabridged Dictionary (1913)

Entozoa \En`to*zo"a\, n. pl. [NL., fr. Gr. ? within + ? an
   animal.] (Zo["o]l.)
   1. A group of worms, including the tapeworms, flukes,
      roundworms, etc., most of which live parasitically in the
      interior of other animals; the Helminthes.

   2. An artificial group, including all kinds of animals living
      parasitically in others.

Entozoon \En`to*zo"["o]n\, n.; pl. {Entozoa}. [NL. See
   {Entozoa}.] (Zo["o]l.)
   One of the Entozoa.

Source : WordNet®

entozoa
     See {entozoan}

entozoan
     adj 1: of or relating to entozoa [syn: {endozoan}]
     2: living within a living animal usually as a parasite;
        "entozoic worms" [syn: {entozoic}, {endozoic}] [ant: {epizoic}]
     n : any of various parasites that live in the internal organs of
         animals (especially intestinal worms) [syn: {endoparasite},
          {entoparasite}, {entozoon}, {endozoan}]
     [also: {entozoa} (pl)]