(n)any of various worms living parasitically in intestines of vertebrates having a retractile proboscis covered with many hooked spines, Syn.spiny-headed worm
The Collaborative International Dictionary of English (GCIDE) v.0.53Collaborative International Dictionary (GCIDE)
‖n. pl. [ NL., from Gr. &unr_; a spine, thorn + &unr_; head. ] (Zool.) A group of intestinal worms, having the proboscis armed with recurved spines. [ 1913 Webster ]