demographer vs population scientist

demographer and population scientist both are nouns.

Word	Noun	Adjective	Verb	Adverb
demographer	Yes	No	No	No
population scientist	Yes	No	No	No

As nouns, demographer and population scientist are synonyms defined as:

demographer and population scientist: a scientist who studies the growth and density of populations and their vital statistics

Other synonyms of demographer include demographist.

demographer (noun)	population scientist (noun)
a scientist who studies the growth and density of populations and their vital statistics	a scientist who studies the growth and density of populations and their vital statistics