subsequent vs posterior

subsequent is not a noun while posterior is a noun.

Word	Noun	Adjective	Verb	Adverb
subsequent	No	Yes	No	No
posterior	Yes	Yes	No	No

subsequent (noun)	posterior (noun)
	the fleshy part of the human body that you sit on
	a tooth situated at the back of the mouth

subsequent (adjective)	posterior (adjective)
following in time or order	located at or near or behind a part or near the end of a structure
	coming at a subsequent time or stage