callousness vs callosity

callousness and callosity both are nouns.

Word	Noun	Adjective	Verb	Adverb
callousness	Yes	No	No	No
callosity	Yes	No	No	No

As nouns, callousness and callosity are synonyms defined as:

callousness and callosity: devoid of passion or feeling; hardheartedness

Other synonyms of callousness include hardness, insensibility, unfeelingness.

callousness (noun)	callosity (noun)
devoid of passion or feeling; hardheartedness	devoid of passion or feeling; hardheartedness
	an area of skin that is thick or hard from continual pressure or friction (as the sole of the foot)