||Hel*min"thes (?), n. pl. [NL., fr.
Gr. &?;, &?;, a worm.] (Zoöl.) One of the grand
divisions or branches of the animal kingdom. It is a large group
including a vast number of species, most of which are parasitic.
Called also Enthelminthes, Enthelmintha.
&fist; The following classes are included, with others of less
importance: Cestoidea (tapeworms), Trematodea (flukes, etc.),
Turbellaria (planarians), Acanthocephala (thornheads), Nematoidea
(roundworms, trichina, gordius), Nemertina (nemerteans). See
Plathelminthes, and Nemathelminthes.