unreal vs imaginary

unreal is not a noun while imaginary is a noun.

Word	Noun	Adjective	Verb	Adverb
unreal	No	Yes	No	No
imaginary	Yes	Yes	No	No

unreal (noun)	imaginary (noun)
	(mathematics) a number of the form a+bi where a and b are real numbers and i is the square root of -1

unreal (adjective)	imaginary (adjective)
lacking in reality or substance or genuineness; not corresponding to acknowledged facts or criteria	not based on fact; existing only in the imagination
not actually such; being or seeming fanciful or imaginary
lacking material form or substance; unreal
contrived by art rather than nature