a life-saver

someone or something that gives you a lot of help when you are in a very difficult situation When you're stuck in traffic like this, a mobile phone's an absolute life-saver.

Common Names:

Name	Pronounced	Usage
Modeste	-	French
BoŻYdar	baw-ZHI-dahr	Polish
Lysimachus	-	Ancient Greek (Latinized)
Tahvo	TAHH-vo	Finnish
SÉAfra	-	Irish
Elizaveta	ye-lee-zah-VYE-tah, ee-lee-zah-VYE-tah	Russian