boniness vs thinness

boniness and thinness both are nouns.

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

As nouns, thinness is a hypernym of boniness; that is, thinness is a word with a broader meaning than boniness:

Other hypernyms of boniness include leanness, spareness.

boniness (noun)	thinness (noun)
extreme leanness (usually caused by starvation or disease)	the property of having little body fat
	relatively small dimension through an object as opposed to its length or width
	a consistency of low viscosity
	the property of being very narrow or thin
	the property of being scanty or scattered; lacking denseness
	The property of lacking substance or strength.