siphonobranchiata

from The Century Dictionary.

• In De Blainville's classification (1825), the first order of his Paracephalophora dioica, containing the “families” Siphonostomata, Entomostomata, and Angiostomata, and contrasted with the order Asiphonobranehiata. See Siphonochlamyda.

from the GNU version of the Collaborative International Dictionary of English.

• noun plural (Zoöl.) A tribe of gastropods having the mantle border, on one or both sides, prolonged in the form of a spout through which water enters the gill cavity. The shell itself is not always siphonostomatous in this group.