ephem·​er·​id i-ˈfe-mə-rəd How to pronounce ephemerid (audio)
: mayfly

Word History


ultimately from Greek ephēmeron

First Known Use

1872, in the meaning defined above

Time Traveler
The first known use of ephemerid was in 1872

Dictionary Entries Near ephemerid

Cite this Entry

“Ephemerid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ephemerid. Accessed 28 Nov. 2023.

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