chambered nautilus noun2 •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.He was still prepared to go on collecting all that life could offer, like a chambered nautilus patiently adding new cells to its slowly expanding spiral. — 1956 •A nautilus of species Nautilus pompilius. formschambered nautili · chambered nautiluses
