stupid vs retarded

stupid and retarded both are nouns.

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

stupid (noun)	retarded (noun)
a person who is not very bright	people collectively who are mentally retarded

stupid (adjective)	retarded (adjective)
lacking or marked by lack of intellectual acuity	relatively slow in mental or emotional or physical development
lacking intelligence
in a state of mental numbness especially as resulting from shock