stupid vs dense

stupid is a noun but dense is not a noun.

Word	Noun	Adjective	Verb	Adverb
stupid	Yes	Yes	No	No
dense	No	Yes	No	No

stupid (noun)	dense (noun)
a person who is not very bright

stupid (adjective)	dense (adjective)
lacking or marked by lack of intellectual acuity	having high relative density or specific gravity
lacking intelligence	hard to pass through because of dense growth
in a state of mental numbness especially as resulting from shock	slow to learn or understand; lacking intellectual acuity
	permitting little if any light to pass through because of denseness of matter
	having component parts closely crowded together