unceasing vs ceaseless

unceasing and ceaseless both are adjectives.

Word	Noun	Adjective	Verb	Adverb
unceasing	No	Yes	No	No
ceaseless	No	Yes	No	No

As adjectives, unceasing and ceaseless are synonyms defined as:

unceasing and ceaseless: uninterrupted in time and indefinitely long continuing

Other synonyms of unceasing include constant, incessant, never-ending, perpetual, unremitting.

unceasing (adjective)	ceaseless (adjective)
uninterrupted in time and indefinitely long continuing	uninterrupted in time and indefinitely long continuing
continuing forever or indefinitely