- a double-ended ship’s boat, constructed, mounted, and provisioned so as to be readily able to rescue and maintain persons from a sinking vessel.
- a similarly constructed boat used by shore-based rescue services.
- a boat, propelled by oars or a motor, used for rescuing people at sea, escaping from a sinking ship, etc
- informal a fund set up by the dealers in a market to rescue any member who may become insolvent as a result of a collapse in market prices
also lifeboat, 1801 (the thing itself attested by 1785), from life (n.) + boat.