contemporaneousness vs contemporaneity

contemporaneousness and contemporaneity both are nouns.

Word	Noun	Adjective	Verb	Adverb
contemporaneousness	Yes	No	No	No
contemporaneity	Yes	No	No	No

As nouns, contemporaneousness and contemporaneity are synonyms defined as:

contemporaneousness and contemporaneity: the quality of being current or of the present

Other synonyms of contemporaneousness include modernism, modernity, modernness.

As nouns, contemporaneousness and contemporaneity are synonyms defined as:

contemporaneousness and contemporaneity: the quality of belonging to the same period of time

contemporaneousness (noun)	contemporaneity (noun)
the quality of being current or of the present	the quality of being current or of the present
the quality of belonging to the same period of time	the quality of belonging to the same period of time