ageless vs aeonian

ageless and aeonian both are adjectives.

Word	Noun	Adjective	Verb	Adverb
ageless	No	Yes	No	No
aeonian	No	Yes	No	No

As adjectives, ageless and aeonian are synonyms defined as:

Other synonyms of ageless include eonian, eternal, everlasting, perpetual, unceasing, unending.

ageless (adjective)	aeonian (adjective)
continuing forever or indefinitely	of or relating to a geological eon (longer than an era)
	continuing forever or indefinitely