Siphonium :: Siphonium (n.) A bony tube which, in some birds, connects the tympanium with the air chambers of the articular piece of the mandible..
Siphonobranchiata :: Siphonobranchiata (n. pl.) 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..
Siphonobranchiate :: Siphonobranchiate (a.) Having a siphon, or siphons, to convey water to the gills; belonging or pertaining to the Siphonobranchiata..
Siphonophora :: Siphonophora (n. pl.) An order of pelagic Hydrozoa including species which form complex free-swimming communities composed of numerous zooids of various kinds, some of which act as floats or as swimming organs, others as feeding or nutritive zooids, and others as reproductive zooids. See Illust. under Physallia, and Porpita..
Siphonopoda :: Siphonopoda (n. pl.) A division of Scaphopoda including those in which the foot terminates in a circular disk.
Siphonostomata :: Siphonostomata (n. pl.) A tribe of parasitic copepod Crustacea including a large number of species that are parasites of fishes, as the lerneans. They have a mouth adapted to suck blood..
Siphonostomata :: Siphonostomata (n. pl.) An artificial division of gastropods including those that have siphonostomatous shells.
Siphonostomatous :: Siphonostomatous (a.) Having the front edge of the aperture of the shell prolonged in the shape of a channel for the protection of the siphon; -- said of certain gastropods.