circus acrobat vs acrobat

circus acrobat and acrobat both are nouns.

Word	Noun	Adjective	Verb	Adverb
circus acrobat	Yes	No	No	No
acrobat	Yes	No	No	No

As nouns, acrobat is a hypernym of circus acrobat; that is, acrobat is a word with a broader meaning than circus acrobat:

circus acrobat: an acrobat who performs acrobatic feats in a circus
acrobat: an athlete who performs acts requiring skill and agility and coordination

circus acrobat (noun)	acrobat (noun)
an acrobat who performs acrobatic feats in a circus	an athlete who performs acts requiring skill and agility and coordination