infant mortality rate vs infant mortality

infant mortality rate and infant mortality both are nouns.

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

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

infant mortality rate and infant mortality: the death rate during the first year of life

Other synonyms of infant mortality rate include infant deathrate.

infant mortality rate (noun)	infant mortality (noun)
the death rate during the first year of life	the death rate during the first year of life