watering hole vs spa

watering hole and spa both are nouns.

Word	Noun	Adjective	Verb	Adverb
watering hole	Yes	No	No	No
spa	Yes	No	No	No

As nouns, watering hole and spa are synonyms defined as:

Other synonyms of watering hole include watering place.

watering hole (noun)	spa (noun)
a health resort near a spring or at the seaside	a fashionable hotel usually in a resort area
	a place of business with equipment and facilities for exercising and improving physical fitness
	a health resort near a spring or at the seaside