deficient vs quantity

deficient is not a noun while quantity is a noun.

Word	Noun	Adjective	Verb	Adverb
deficient	No	Yes	No	No
quantity	Yes	No	No	No

deficient (noun)	quantity (noun)
	how much there is or how many there are of something that you can quantify
	an adequate or large amount
	the concept that something has a magnitude and can be represented in mathematical expressions by a constant or a variable

deficient (adjective)	quantity (adjective)
of a quantity not able to fulfill a need or requirement
inadequate in amount or degree
falling short of some prescribed norm