inhumanity vs barbarism

inhumanity and barbarism both are nouns.

Word	Noun	Adjective	Verb	Adverb
inhumanity	Yes	No	No	No
barbarism	Yes	No	No	No

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

Other hyponyms of inhumanity include barbarity, brutality, savagery, outrage, enormity.

inhumanity (noun)	barbarism (noun)
an act of atrocious cruelty	a brutal barbarous savage act
the quality of lacking compassion or consideration for others