Adjective

1. Describing that which preserves life, that prevents death.

   The lifesaving surgery was expensive, but so is a funeral.

Usage notes

• “Life-saving” is significantly more commonly used than “lifesaving” as adjective.

Noun

1. The act of saving a life, especially from drowning.

   I’m normally a big fan of lifesaving, but in his case we can make an exception.