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.
The Bethany Beach firefly isn’t the only one that has been targeted for protection. Alexa Robles-Gil, Smithsonian Magazine, 1 Oct. 2024 There are also moments of beauty: The sequence in which Claire and Oliver finally encounter the fireflies on Jeju unites set, video, and lights (by Ben Stanton) in a luscious swirl while also bringing a section of the production’s orchestra onstage to striking effect. Sara Holdren, Vulture, 12 Nov. 2024 Building on a past analysis of the first firefly species identified from that era, initially described in 2015, a separate team of scientists investigated another 99 million-year-old firefly trapped in tree resin. Jackie Wattles, CNN, 26 Oct. 2024 Daryl had been reminded to bet on hope by a vision of Isabelle, who’d then vanished in a puff of fireflies. Charlie Mason, TVLine, 3 Nov. 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 Dec. 2024.

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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