salon vs beauty salon

salon and beauty salon both are nouns.

Word	Noun	Adjective	Verb	Adverb
salon	Yes	No	No	No
beauty salon	Yes	No	No	No

As nouns, salon and beauty salon are synonyms defined as:

Other synonyms of salon include beauty parlor, beauty parlour, beauty shop.

salon (noun)	beauty salon (noun)
elegant sitting room where guests are received	a shop where hairdressers and beauticians work
gallery where works of art can be displayed
a shop where hairdressers and beauticians work