astronomer vs stargazer

astronomer and stargazer both are nouns.

Word	Noun	Adjective	Verb	Adverb
astronomer	Yes	No	No	No
stargazer	Yes	No	No	No

As nouns, astronomer and stargazer are synonyms defined as:

Other synonyms of astronomer include uranologist.

astronomer (noun)	stargazer (noun)
a physicist who studies astronomy	heavy-bodied marine bottom-lurkers with eyes on flattened top of the head
	a physicist who studies astronomy
	someone indifferent to the busy world