unfeelingness vs insensitivity

unfeelingness and insensitivity both are nouns.

Word	Noun	Adjective	Verb	Adverb
unfeelingness	Yes	No	No	No
insensitivity	Yes	No	No	No

As nouns, insensitivity is a hypernym of unfeelingness; that is, insensitivity is a word with a broader meaning than unfeelingness:

unfeelingness: devoid of passion or feeling; hardheartedness
insensitivity: the inability to respond to affective changes in your interpersonal environment

Other hypernyms of unfeelingness include insensitiveness.

unfeelingness (noun)	insensitivity (noun)
devoid of passion or feeling; hardheartedness	the inability to respond to affective changes in your interpersonal environment