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
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Recent Examples of firefly from the Web
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Attendance at Fireflies home games is up nearly 40 percent, according to Baseball America.
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Each photo where the firefly lights become trails is just one long exposure.
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.
Illustration of firefly
First Known Use of firefly
1655
FIREFLY Defined for English Language Learners
firefly
playDefinition of firefly for English Language Learners
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: a small flying insect that produces a soft light
FIREFLY Defined for Kids
firefly
playDefinition of firefly for Students
fireflies
: a small beetle producing a soft light
Learn More about firefly
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See 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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