1.NounSomeone or something that saves lives.
A lifeguard or other rescuer.
"My dad loves his job as a surf lifesaver.; Paramedics are not just ordinary workers but lifesavers with a very important job.; They threw him a lifesaver and then hauled him up onto the boat.; When I got lost in the woods, my Swiss Army knife was a lifesaver."
2.NounA lifeguard or other rescuer.
"My dad loves his job as a surf lifesaver.; Paramedics are not just ordinary workers but lifesavers with a very important job."
3.NounA life buoy.
"They threw him a lifesaver and then hauled him up onto the boat."
4.NounAny lifesaving tool or item of supplies.
"When I got lost in the woods, my Swiss Army knife was a lifesaver."
5.NounSomeone or something that is very useful or helpful.
"Thank you so much for fixing my car; you're a real lifesaver!; This shop is a lifesaver on a hot day when you're craving a cold drink."