hilliness vs ruggedness

hilliness and ruggedness both are nouns.

Word	Noun	Adjective	Verb	Adverb
hilliness	Yes	No	No	No
ruggedness	Yes	No	No	No

As nouns, ruggedness is a hypernym of hilliness; that is, ruggedness is a word with a broader meaning than hilliness:

hilliness (noun)	ruggedness (noun)
the quality of being hilly	the property of being big and strong
	the quality of being topologically uneven
	the quality of being difficult to do