posterior vs sexual activity

posterior and sexual activity both are nouns.

Word	Noun	Adjective	Verb	Adverb
posterior	Yes	Yes	No	No
sexual activity	Yes	No	No	No

posterior (noun)	sexual activity (noun)
the fleshy part of the human body that you sit on	activities associated with sexual intercourse
a tooth situated at the back of the mouth

posterior (adjective)	sexual activity (adjective)
located at or near or behind a part or near the end of a structure
coming at a subsequent time or stage