viciousness vs harshness

viciousness and harshness both are nouns.

Word	Noun	Adjective	Verb	Adverb
viciousness	Yes	No	No	No
harshness	Yes	No	No	No

As nouns, harshness is a hypernym of viciousness; that is, harshness is a word with a broader meaning than viciousness:

Other hypernyms of viciousness include cruelness, cruelty.

viciousness (noun)	harshness (noun)
the trait of extreme cruelty	the quality of being harsh or rough or grating to the senses
	excessive sternness
	the roughness of a substance that causes abrasions
	the quality of being cruel and causing tension or annoyance