facial vs beauty treatment

facial and beauty treatment both are nouns.

Word	Noun	Adjective	Verb	Adverb
facial	Yes	Yes	No	No
beauty treatment	Yes	No	No	No

As nouns, beauty treatment is a hypernym of facial; that is, beauty treatment is a word with a broader meaning than facial:

facial: care for the face that usually involves cleansing and massage and the application of cosmetic creams
beauty treatment: enhancement of someone's personal beauty

Other hypernyms of facial include skin care, skincare.

facial (noun)	beauty treatment (noun)
care for the face that usually involves cleansing and massage and the application of cosmetic creams	enhancement of someone's personal beauty
cranial nerve that supplies facial muscles

facial (adjective)	beauty treatment (adjective)
of or concerning the face
of or pertaining to the outside surface of an object