1. a spherical deep-sea observation chamber that is lowered by cable from a ship
Usage: oceanography

Examples

• The scientists descended in a bathysphere to study deep-sea creatures.
• William Beebe made famous dives in his bathysphere during the 1930s.
• The bathysphere was lowered 3,000 feet below the ocean surface.
• Through the bathysphere’s thick windows, they observed bioluminescent fish.
• The steel bathysphere protected the researchers from crushing water pressure.
• Modern submersibles have largely replaced the traditional bathysphere design.