coffee bar vs coffeehouse

coffee bar and coffeehouse both are nouns.

Word	Noun	Adjective	Verb	Adverb
coffee bar	Yes	No	No	No
coffeehouse	Yes	No	No	No

As nouns, coffee bar and coffeehouse are synonyms defined as:

coffee bar and coffeehouse: a small restaurant where drinks and snacks are sold

Other synonyms of coffee bar include cafe, coffee shop.

coffee bar (noun)	coffeehouse (noun)
a small restaurant where drinks and snacks are sold	a small restaurant where drinks and snacks are sold