lifeboat
noun [ C ] uk/ˈlaɪf.bəʊt/ us/ˈlaɪf.boʊt/
（用于救援生命有危险的人的）救生船，救生筏
a large boat that is kept ready to go out and save people who are in danger in the water
（配在船上供逃生用的）救生船，救生筏
a small boat kept on a ship for people to leave in if the ship is not safe or might sink