firefly

noun
fire·​fly | \ ˈfī(-ə)r-ˌflī How to pronounce firefly (audio) \

Definition of firefly

: 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

Today’s first plate featured kawahagi, tilefish, topped with its own liver; toro, ultra-fatty tuna; grilled sawara, Spanish mackerel; and stewed hotari-ika, firefly squid. Tom Downey, WSJ, "A Sushi-Obsessed Trip to Osaka," 4 Dec. 2018 Among fireflies, however, villains hide among the artists. Katherine J. Wu, Smithsonian, "Why Bioluminescence Evolved to Be Red Light, and Blue," 26 June 2018 One of the biggest threats to fireflies is habitat loss. Rebecca Straus, Good Housekeeping, "5 Ways to Attract Fireflies to Your Yard," 19 July 2018 The stars were brilliant like a blizzard of fireflies in the night. Caroline Hallemann, Town & Country, "Read the Full Transcript of George P. Bush's Eulogy for His Grandfather, George H.W. Bush," 6 Dec. 2018 Traveling during the summer to conduct field work, Shimomura studied bioluminescent fireworms in Bermuda, cave worms and limpets in New Zealand, and a plethora of glowing bacteria, twinkling fireflies and neon-colored squid and krill. Harrison Smith, The Seattle Times, "Osamu Shimomura, atomic blast survivor and Nobel-winning chemist, dies at 90," 23 Oct. 2018 High grasses and shrubbery are a key part of a firefly’s ideal habitat. Rebecca Straus, Good Housekeeping, "5 Ways to Attract Fireflies to Your Yard," 19 July 2018 But if the brightest fireflies instead converge at the jar’s bottom and top, its glow will peak at those points instead. Shannon Hall, Scientific American, "The Sun Is Spitting Out Strange Patterns of Gamma Rays—and No One Knows Why," 28 Mar. 2018 There were also fireflies everywhere on the big lawn, which the children chased around all evening once the weather cleared. Fortune, "'Glamping' Has Officially Come to New York City," 12 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'firefly.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of firefly

1655, in the meaning defined above

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Statistics for firefly

Last Updated

14 Feb 2019

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Time Traveler for firefly

The first known use of firefly was in 1655

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More Definitions for firefly

firefly

noun

English Language Learners Definition of firefly

: a small flying insect that produces a soft light

firefly

noun
fire·​fly | \ ˈfīr-ˌflī How to pronounce firefly (audio) \
plural fireflies

Kids Definition of firefly

: a small beetle producing a soft light

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More from Merriam-Webster on firefly

Rhyming Dictionary: Words that rhyme with firefly

Spanish Central: Translation of firefly

Nglish: Translation of firefly for Spanish Speakers

Britannica English: Translation of firefly for Arabic Speakers

Britannica.com: Encyclopedia article about firefly

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