poorness vs thinness

poorness and thinness both are nouns.

Word	Noun	Adjective	Verb	Adverb
poorness	Yes	No	No	No
thinness	Yes	No	No	No

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

Other hyponyms of poorness include wateriness, abstemiousness, spareness, sparseness, sparsity.

poorness (noun)	thinness (noun)
the quality of being poorly made or maintained	the property of having little body fat
less than adequate	relatively small dimension through an object as opposed to its length or width
the quality of being meager	a consistency of low viscosity
the state of having little or no money and few or no material possessions	the property of being very narrow or thin
	the property of being scanty or scattered; lacking denseness
	The property of lacking substance or strength.