A person who rescues people from drowning, especially at a beach or pool; or something that helps you out of a difficult situation.
Lifesaver is a compound of 'life' and 'saver' (one who saves). The original meaning referred to people trained to rescue swimmers, and it metaphorically extended to mean anything that rescues you from trouble.
The Lifesavers candy brand got its name in 1912 because the circular mint candy with a hole in the middle looks like an actual life preserver ring—it's one of the best examples of a brand name based on a visual pun.
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