economist vs social scientist

economist and social scientist both are nouns.

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

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

economist: an expert in the science of economics
social scientist: someone expert in the study of human society and its personal relationships

economist (noun)	social scientist (noun)
an expert in the science of economics	someone expert in the study of human society and its personal relationships