incessancy vs ceaselessness

incessancy and ceaselessness both are nouns.

Word	Noun	Adjective	Verb	Adverb
incessancy	Yes	No	No	No
ceaselessness	Yes	No	No	No

As nouns, incessancy and ceaselessness are synonyms defined as:

incessancy and ceaselessness: the quality of something that continues without end or interruption

Other synonyms of incessancy include continuousness, incessantness.

incessancy (noun)	ceaselessness (noun)
the quality of something that continues without end or interruption	the quality of something that continues without end or interruption