echiuroidea
Ech`i*u*roi"de*a, n. pl. Etym: [NL., fr. echiurus, the name of one genus (Gr. -oid.] (Zoöl.) Defn: A division of Annelida which includes the genus Echiurus and allies. They are often classed among the Gephyrea, and called the armed Gephyreans.