disparity vs imbalance

disparity and imbalance both are nouns.

Word	Noun	Adjective	Verb	Adverb
disparity	Yes	No	No	No
imbalance	Yes	No	No	No

As nouns, imbalance is a hyponym of disparity; that is, imbalance is a word with a more specific, narrower meaning than disparity:

Other hyponyms of disparity include far cry, gap, spread, disconnect, disconnection, gulf, disproportion, dissymmetry.

disparity (noun)	imbalance (noun)
inequality or difference in some respect	lack of proportion; imbalance among the parts of something
	a lack of balance or state of disequilibrium