mortality rate vs mortality

mortality rate and mortality both are nouns.

Word	Noun	Adjective	Verb	Adverb
mortality rate	Yes	No	No	No
mortality	Yes	No	No	No

As nouns, mortality rate and mortality are synonyms defined as:

mortality rate and mortality: the ratio of deaths in an area to the population of that area; expressed per 1000 per year

Other synonyms of mortality rate include death rate, deathrate, fatality rate.

mortality rate (noun)	mortality (noun)
the ratio of deaths in an area to the population of that area; expressed per 1000 per year	the quality or state of being mortal
	the ratio of deaths in an area to the population of that area; expressed per 1000 per year