| Noun | 1. | Acanthocephala - phylum or class of elongated wormlike parasites that live in the intestines of vertebrates: spiny-headed wormsanimal kingdom, Animalia, kingdom Animalia - taxonomic kingdom comprising all living or extinct animals acanthocephalan, spiny-headed worm - any of various worms living parasitically in intestines of vertebrates having a retractile proboscis covered with many hooked spines phylum - (biology) the major taxonomic group of animals and plants; contains classes |