poor vs poorly

poor is a noun but poorly is not a noun.

Word	Noun	Adjective	Verb	Adverb
poor	Yes	Yes	No	No
poorly	No	Yes	No	Yes

poor (noun)	poorly (noun)
people without possessions or wealth (considered as a group)

poor (adjective)	poorly (adjective)
having little money or few possessions	somewhat ill or prone to illness
lacking in quality or substances
characterized by or indicating poverty
of insufficient quantity to meet a need
deserving or inciting pity

poor (adverb)	poorly (adverb)
	(`ill' is often used as a combining form) in a poor or improper or unsatisfactory manner; not well