firefly

noun

fire·​fly ˈfī(-ə)r-ˌflī How to pronounce firefly (audio)
: any of various winged nocturnal beetles (especially family Lampyridae) that produce a bright soft intermittent light by oxidation of luciferin especially for courtship purposes

Illustration of firefly

Illustration of firefly

Examples of firefly 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.
Looking for love National Geographic/Stephen Alvarez A glowing firefly flying through the forest at night. Ars Technica, 14 Jan. 2025 Lucky for Southerners, our region is home to all kinds of one-of-a-kind natural experience—from catching the synchronous fireflies in Great Smoky Mountain National Park or Congaree National Park to kayaking to see bioluminescent plankton in Vero Beach, Florida. Tara Massouleh McCay, Southern Living, 26 Dec. 2024 Scientists have now discovered a fascinating new example – some spiders have been seen manipulating fireflies’ flashes to attract more bugs to their webs. New Atlas, 31 Dec. 2024 After reportedly leaving to go to catch fireflies, Morgan was never seen again. Liam Quinn, People.com, 1 Oct. 2024 See all Example Sentences for firefly 

Word History

First Known Use

1655, in the meaning defined above

Time Traveler
The first known use of firefly was in 1655

Dictionary Entries Near firefly

Cite this Entry

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

Kids Definition

firefly

noun
fire·​fly ˈfī(ə)r-ˌflī How to pronounce firefly (audio)
: any of numerous night-flying beetles that produce a bright soft flashing light for courtship purposes

More from Merriam-Webster on firefly

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