Helminthes n. pl. (Zool.) 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. Note: 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.
