nautilus
Pronunciation:
/ˈnɔː.tɪ.ləs//ˈnɑ.tɪ.ləs/noun
Definitions
A marine mollusc, of the family Nautilidae native to the Pacific Ocean and Indian Ocean, which has tentacles and a spiral shell with a series of air-filled chambers, of which Nautilus is the type genus.
A kind of diving bell that sinks or rises by means of compressed air.