mayfly

noun

may·​fly ˈmā-ˌflī How to pronounce mayfly (audio)
: any of an order (Ephemeroptera) of insects with an aquatic nymph and a short-lived, fragile adult lacking mouthparts and having membranous, heavily veined wings and two or three long, threadlike tails

Note: the wings of the mayfly are held vertically above the body when closed.

called also ephemerid

Illustration of mayfly

Illustration of mayfly

Examples of mayfly in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In the fast-moving air taxi and eVTOL market, things are jumping at a pace not seen since the dotcom bubble of the 1990s when flash new companies had the lifespan of mayflies with a chronic cough. David Szondy, New Atlas, 5 Jan. 2025 Keep the rig small; mayfly larvae are rarely longer than an inch. Alex Robinson, Outdoor Life, 13 June 2024 Starting in May and running through September, mayflies emerge all across North America. Shaye Baker, Field & Stream, 6 June 2024 Below is a quick guide to mayfly basics, hatch timing and location, and mayfly fishing tips. Shaye Baker, Field & Stream, 6 June 2024 See all Example Sentences for mayfly 

Word History

First Known Use

circa 1653, in the meaning defined above

Time Traveler
The first known use of mayfly was circa 1653

Dictionary Entries Near mayfly

Cite this Entry

“Mayfly.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mayfly. Accessed 20 Jan. 2025.

Kids Definition

mayfly

noun
may·​fly -ˌflī How to pronounce mayfly (audio)
: any of a group of insects that as adults live only a short time and have fragile wings

More from Merriam-Webster on mayfly

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