clarity vs clearness

clarity and clearness both are nouns.

Word	Noun	Adjective	Verb	Adverb
clarity	Yes	No	No	No
clearness	Yes	No	No	No

As nouns, clarity and clearness are synonyms defined as:

Other synonyms of clarity include uncloudedness.

As nouns, clarity and clearness are synonyms defined as:

clarity and clearness: free from obscurity and easy to understand; the comprehensibility of clear expression

Other synonyms of clarity include limpidity, lucidity, lucidness, pellucidity.

clarity (noun)	clearness (noun)
the quality of clear water	free from obscurity and easy to understand; the comprehensibility of clear expression
free from obscurity and easy to understand; the comprehensibility of clear expression	the quality of clear water