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.
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 Other elements included the building of a practical mud pit, mushrooms on set and real fireflies for a sequence in Episode 3, to ensure each moment in the series looked and felt as real as possible. Andrés Buenahora, Variety, 30 Oct. 2024 This specimen, found in northern Myanmar in 2016, may help researchers better understand how fireflies evolved the ability to glow at least 100 million years ago. Jackie Wattles, CNN, 26 Oct. 2024 For many of us, our first exposure to death involved an animal: the firefly in the Mason jar, the bird beneath the window, the deer beside the highway, the beloved cat gone gaunt with age, curled up stiff below the basement stairs. Kathryn Schulz, The New Yorker, 28 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 24 Nov. 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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