The name Nautilus can refer to more than one thing:

• "Nautilos" is a Greek word for a sailor or a ship.
• A nautilus is a cephalopod with a many-chambered, spiral shell with a pearly interior.
• Nautilus has been used as names for many ships and submarines:
  • Nautilus, the first practical submarine, was invented by Robert Fulton in 1800.
  • Six vessels of the United States Navy have been named USS Nautilus, including Nautilus (SSN-571), the first nuclear-powered submarine.
  • The fictional submarine Nautilus features in the 1870 novel 20,000 Leagues Under the Sea by Jules Verne.
  • One ship of the British Royal Navy has been named HMS Nautilus.
  • The submarine USS O-12 (SS-73) was decomissioned, converted for use by Sir Hubert Wilkins's Arctic Expedition, and renamed Nautilus.
• Nautilus speakers are made by B&W.
• Nautilus Group is a weight training equipment manufacturer, founded by Arthur Jones, which markets the Bowflex and a line of isotonic exercise machines whose mechanisms include oval cams.
• Nautilus is a furry science fiction comic.
• Nautilus is a submarine-themed German-style board game.
• The Nautilus file manager is used in the GNOME desktop environment.