familiarity vs casualness

familiarity and casualness both are nouns.

Word	Noun	Adjective	Verb	Adverb
familiarity	Yes	No	No	No
casualness	Yes	No	No	No

As nouns, familiarity and casualness are synonyms defined as:

familiarity (noun)	casualness (noun)
an act of undue intimacy	a casual manner
usualness by virtue of being familiar or well known	The state of coming without regularity; of being occasional or incidental.
close or warm friendship
a casual manner
personal knowledge or information about someone or something