ephemeral vs ephemeron

ephemeral and ephemeron both are nouns.

Word	Noun	Adjective	Verb	Adverb
ephemeral	Yes	Yes	No	No
ephemeron	Yes	No	No	No

As nouns, ephemeral and ephemeron are synonyms defined as:

ephemeral and ephemeron: anything short-lived, as an insect that lives only for a day in its winged form

ephemeral (noun)	ephemeron (noun)
anything short-lived, as an insect that lives only for a day in its winged form	anything short-lived, as an insect that lives only for a day in its winged form

ephemeral (adjective)	ephemeron (adjective)
lasting a very short time