Saturn UK /ˈsæt.ən/US /ˈsæt.ɚn/ noun4 •The sixth planet of the solar system, known for its large rings, and until recent times the furthest known; represented in astronomy and astrology by ♄. •A car of the former Saturn brand by GM.Remember that guy who worked in the warehouse who used to drive that blue Saturn? That guy was the best. I wonder where he is now? •(rare) Sable (black), in the postmedieval practice of blazoning the tinctures in the arms of certain sovereign people and places as planets. •(no longer used) Lead (the metal).