geologic time vs eon

geologic time and eon both are nouns.

Word	Noun	Adjective	Verb	Adverb
geologic time	Yes	No	No	No
eon	Yes	No	No	No

As nouns, eon is a hyponym of geologic time; that is, eon is a word with a more specific, narrower meaning than geologic time:

geologic time: the time of the physical formation and development of the earth (especially prior to human history)
eon: the longest division of geological time

Other hyponyms of geologic time include aeon, geological period, period, era, geological era, epoch.

geologic time (noun)	eon (noun)
the time of the physical formation and development of the earth (especially prior to human history)	(Gnosticism) a divine power or nature emanating from the Supreme Being and playing various roles in the operation of the universe
	an immeasurably long period of time
	the longest division of geological time