variety vs heterogeneousness

variety and heterogeneousness both are nouns.

Word	Noun	Adjective	Verb	Adverb
variety	Yes	No	No	No
heterogeneousness	Yes	No	No	No

As nouns, heterogeneousness is a hypernym of variety; that is, heterogeneousness is a word with a broader meaning than variety:

Other hypernyms of variety include heterogeneity.

variety (noun)	heterogeneousness (noun)
noticeable heterogeneity	the quality of being diverse and not comparable in kind
a difference that is usually pleasant
a category of things distinguished by some common characteristic or quality
a show consisting of a series of short unrelated performances
(biology) a taxonomic category consisting of members of a species that differ from others of the same species in minor but heritable characteristics
a collection containing a variety of sorts of things