suffering vs miserableness

suffering and miserableness both are nouns.

Word	Noun	Adjective	Verb	Adverb
suffering	Yes	Yes	No	No
miserableness	Yes	No	No	No

As nouns, miserableness is a hypernym of suffering; that is, miserableness is a word with a broader meaning than suffering:

Other hypernyms of suffering include misery, wretchedness.

suffering (noun)	miserableness (noun)
feelings of mental or physical pain	a state of ill-being due to affliction or misfortune
psychological suffering
a state of acute pain
misery resulting from affliction

suffering (adjective)	miserableness (adjective)
troubled by pain or loss
very unhappy; full of misery