ephemeron

noun

ephem·​er·​on

ə̇ˈfeməˌrän

plural ephemera -m(ə)rə  also ephemerons

-məˌränz

1

: ephemerid

2

: ephemeral entry 2

Word History

Etymology

New Latin, from Greek ephemēron May fly, from neuter of ephemēros lasting a day, short-lived, daily

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