inadequate vs poor

inadequate is not a noun while poor is a noun.

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

As adjectives, inadequate and poor are synonyms defined as:

Other synonyms of inadequate include jejune, short.

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

inadequate (adjective)	poor (adjective)
lacking the requisite qualities or resources to meet a task	having little money or few possessions
of insufficient quantity to meet a need	lacking in quality or substances
	characterized by or indicating poverty
	of insufficient quantity to meet a need
	deserving or inciting pity