sociologist vs social scientist

sociologist and social scientist both are nouns.

Word	Noun	Adjective	Verb	Adverb
sociologist	Yes	No	No	No
social scientist	Yes	No	No	No

As nouns, social scientist is a hypernym of sociologist; that is, social scientist is a word with a broader meaning than sociologist:

sociologist: a social scientist who studies the institutions and development of human society
social scientist: someone expert in the study of human society and its personal relationships

sociologist (noun)	social scientist (noun)
a social scientist who studies the institutions and development of human society	someone expert in the study of human society and its personal relationships