synchroneity vs synchronism

synchroneity and synchronism both are nouns.

Word	Noun	Adjective	Verb	Adverb
synchroneity	Yes	No	No	No
synchronism	Yes	No	No	No

As nouns, synchroneity and synchronism are synonyms defined as:

synchroneity and synchronism: the relation that exists when things occur at the same time

Other synonyms of synchroneity include synchronicity, synchronisation, synchronization, synchronizing, synchrony.

synchroneity (noun)	synchronism (noun)
the relation that exists when things occur at the same time	the relation that exists when things occur at the same time