badness vs raininess

badness and raininess both are nouns.

Word	Noun	Adjective	Verb	Adverb
badness	Yes	No	No	No
raininess	Yes	No	No	No

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

Other hyponyms of badness include foulness, distressfulness, seriousness.

badness (noun)	raininess (noun)
that which is below standard or expectations as of ethics or decency	(of weather) the badness of the weather
used of the degree of something undesirable e.g. pain or weather
an attribute of mischievous children