ultimacy vs ultimateness

ultimacy and ultimateness both are nouns.

Word	Noun	Adjective	Verb	Adverb
ultimacy	Yes	No	No	No
ultimateness	Yes	No	No	No

As nouns, ultimacy and ultimateness are synonyms defined as:

ultimacy and ultimateness: the state or degree of being ultimate; the final or most extreme in degree or size or time or distance

ultimacy (noun)	ultimateness (noun)
the state or degree of being ultimate; the final or most extreme in degree or size or time or distance	the state or degree of being ultimate; the final or most extreme in degree or size or time or distance