cruelness vs savagery

cruelness and savagery both are nouns.

Word	Noun	Adjective	Verb	Adverb
cruelness	Yes	No	No	No
savagery	Yes	No	No	No

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

Other hyponyms of cruelness include brutality, ferociousness, viciousness, murderousness.

cruelness (noun)	savagery (noun)
the quality of being cruel and causing tension or annoyance	a brutal barbarous savage act
	the trait of extreme cruelty
	the property of being untamed and ferocious