En`to*zo"a (?), n. pl. [NL., fr. Gr. within + an animal.] Zool.
A group of worms, including the tapeworms, flukes, roundworms, etc., most of which live parasitically in the interior of other animals; the Helminthes.
An artificial group, including all kinds of animals living parasitically in others.
© Webster 1913.