Torus-shaped object of density low enough to keep a person, who usually slips his head, shoulders, and arms through it, afloat.(noun)
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Use "life-buoy" in a sentence
""Mrs. Duncan," was Duncan's reply, as he tore the life-buoy from its hook and flung it aft."
"Mapuhi and his wife survive amid the broken bodies littering the island but his mother Nauri is missing, swept away, forming a life-buoy out of floating cocoanuts and drifting to a tiny island fifteen miles from Hikueru where she is tormented by the corpses washing ashore."
"If there is a man overboard, he must have my life-buoy; but that does not make the whole ship common property."