Illustration of firefly
firefly
noun
fire·fly
ˈfī(-ə)r-ˌflī 
: any of various winged nocturnal beetles (especially family Lampyridae) that produce a bright soft intermittent light by oxidation of luciferin especially for courtship purposes
Examples of firefly in a Sentence
Recent Examples on the Web
Goree remembers her town through images of crickets singing and fireflies lighting up the night sky.
—
Ignacio Calderon, USA Today, 23 May 2025
Held in the heart of the Allegheny National Forest, these gatherings are part fundraiser, part firefly conservation event (and fully magical to boot).
—Allison Palmer, Sacbee.com, 21 May 2025
Guests will look for fireflies and participate in glow-in-the-dark activities from 6 to 8 p.m. Friday, June 6.
—Monica Hooper, Arkansas Online, 17 May 2025
In a forest space, beams of light shoot past like a long-exposure photo of fireflies.
—Lisa Lucas, New York Times, 16 May 2025
See All Example Sentences for firefly
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.
Ignacio Calderon, USA Today, 23 May 2025
Held in the heart of the Allegheny National Forest, these gatherings are part fundraiser, part firefly conservation event (and fully magical to boot).
—Allison Palmer, Sacbee.com, 21 May 2025
Guests will look for fireflies and participate in glow-in-the-dark activities from 6 to 8 p.m. Friday, June 6.
—Monica Hooper, Arkansas Online, 17 May 2025
In a forest space, beams of light shoot past like a long-exposure photo of fireflies.
—Lisa Lucas, New York Times, 16 May 2025
See All Example Sentences for firefly
Cite this Entry
“Firefly.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/firefly. Accessed 1 Jun. 2025.
Copy CitationKids Definition
firefly
noun
fire·fly
ˈfī(ə)r-ˌflī
: any of numerous night-flying beetles that produce a bright soft flashing light for courtship purposes
Love words? Need even more definitions?
Merriam-Webster unabridged
Share