I. ˈlife-ˌsaving 1 BrE AmE , life‧sav‧ing /ˈlaɪfˌseɪvɪŋ/ adjective [only before noun]
life-saving medical treatments or equipment are used to help save people’s lives
lifesaving surgery/treatment/drugs etc
The boy needs a life-saving transplant operation.
II. life-saving 2 BrE AmE , life‧sav‧ing /ˈlaɪfˌseɪvɪŋ/ noun [uncountable]
the skills necessary to save a person from drowning:
All of the staff have been trained in lifesaving.