lifesaver

Từ điển WordNet v3.1 - WordNet Dictionary

noun

1. a life preserver in the form of a ring of buoyant material
• Syn:
life buoy, life belt, life ring
• Hypernyms:
life preserver, preserver, flotation device
• Hyponyms:
breeches buoy
2. an attendant employed at a beach or pool to protect swimmers from accidents
• Syn:
lifeguard
• Hypernyms:
attendant, attender, tender