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
Example Sentences
Recent Examples on the Web During her research, Vaz discovered conservation units were not protecting firefly populations from light pollution. 
Karl Schneider, The Indianapolis Star, 13 Sep. 2022 See different species of colorful beetles, ants and an ant mound, a cicada, butterflies, a firefly, a stink bug, a ladybug, a peacock jumping spider, a dragonfly, a walking stick, a katydid, a caterpillar and a hissing cockroach. The Courier-Journal, 31 Aug. 2022 These include the Bethany Beach firefly (Photuris bethaniensis), which is only found along the Atlantic coastline in Delaware, according to The Xerces Society. Sarah Bowman, USA TODAY, 2 July 2022 The Cypress firefly, a species recently discovered to be in Indiana, falls into this third category. Sarah Bowman, The Indianapolis Star, 28 June 2022 Create a firefly haven in your yard by turning it into a certified habitat (complete with a sign!). Bryce Jones, Better Homes & Gardens, 2 Aug. 2022 The Great Smoky Mountains National Park, which borders North Carolina and Tennessee, is gearing up for its annual synchronous firefly event. Kelly Corbett, House Beautiful, 24 Mar. 2022 The females of one firefly species have earned the nickname femme fatales. Sarah Bowman, The Indianapolis Star, 29 June 2022 Researchers in this study found that firefly occurrences (as observed by their flash patterns) depend on proximity to light. Shreya Sharma, Quartz, 24 June 2022 See More
Karl Schneider, The Indianapolis Star, 13 Sep. 2022 See different species of colorful beetles, ants and an ant mound, a cicada, butterflies, a firefly, a stink bug, a ladybug, a peacock jumping spider, a dragonfly, a walking stick, a katydid, a caterpillar and a hissing cockroach. The Courier-Journal, 31 Aug. 2022 These include the Bethany Beach firefly (Photuris bethaniensis), which is only found along the Atlantic coastline in Delaware, according to The Xerces Society. Sarah Bowman, USA TODAY, 2 July 2022 The Cypress firefly, a species recently discovered to be in Indiana, falls into this third category. Sarah Bowman, The Indianapolis Star, 28 June 2022 Create a firefly haven in your yard by turning it into a certified habitat (complete with a sign!). Bryce Jones, Better Homes & Gardens, 2 Aug. 2022 The Great Smoky Mountains National Park, which borders North Carolina and Tennessee, is gearing up for its annual synchronous firefly event. Kelly Corbett, House Beautiful, 24 Mar. 2022 The females of one firefly species have earned the nickname femme fatales. Sarah Bowman, The Indianapolis Star, 29 June 2022 Researchers in this study found that firefly occurrences (as observed by their flash patterns) depend on proximity to light. Shreya Sharma, Quartz, 24 June 2022 See More Word History
First Known Use
1655, in the meaning defined above
Kids Definition
firefly
noun
fire·fly ˈfīr-ˌflī
plural fireflies
: a small beetle producing a soft light