life preserver
中文翻译
n. <美>救生工具, <英>（用以自卫的）护身棒
常见例句
1
n an attendant employed at a beach or pool to protect swimmers from accidents n a life preserver in the form of a ring of buoyant material
2
plural of lifesaver n an attendant employed at a beach or pool to protect swimmers from accidents n a life preserver in the form of a ring of buoyant material