lifesaver vs attender

lifesaver and attender both are nouns.

Word	Noun	Adjective	Verb	Adverb
lifesaver	Yes	No	No	No
attender	Yes	No	No	No

As nouns, attender is a hypernym of lifesaver; that is, attender is a word with a broader meaning than lifesaver:

lifesaver: an attendant employed at a beach or pool to protect swimmers from accidents
attender: someone who waits on or tends to or attends to the needs of another

Other hypernyms of lifesaver include attendant, tender.

lifesaver (noun)	attender (noun)
a life preserver in the form of a ring of buoyant material	someone who waits on or tends to or attends to the needs of another
an attendant employed at a beach or pool to protect swimmers from accidents	a person who is present and participates in a meeting
	someone who listens attentively