gad·​fly ˈgad-ˌflī How to pronounce gadfly (audio)
: any of various flies (such as a horsefly, botfly, or warble fly) that bite or annoy livestock
: a person who stimulates or annoys other people especially by persistent criticism
a political gadfly

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The Gadfly of Athens

The history of gadfly starts with gad, which now means "chisel" but which formerly could designate a spike, spear, or rod for goading cattle. Late in the 16th century, gad was joined with fly to designate any of several insects that aggravate livestock. Before too long, we began applying gadfly to people who annoy or provoke others. One of history's most famous gadflies was the philosopher Socrates, who was known for his constant questioning of his fellow Athenians' ethics, misconceptions, and assumptions. In his Apology, Plato describes Socrates' characterization of Athens as a large and sluggish horse and of Socrates himself as the fly that bites and rouses it. Many translations use gadfly in this portion of the Apology, and Socrates is sometimes referred to as the "gadfly of Athens."

Examples of gadfly in a Sentence

the journalist was known as a gadfly for exposing hypocrisy in politics
Recent Examples on the Web Along with being a social gadfly, Truman was an ambitious writer. TIME, 31 Jan. 2024 However, activists and gadflies that may own a single share of stock are at the ready, seeking to be the center of attention and perhaps even disrupting the meeting. Richard Torrenzano, Fortune, 18 Jan. 2024 As Ginsberg was something of an amateur photographer and all-around gadfly, there are photos of Iggy Pop, Marianne Faithfull, Lou Reed and more among his souvenirs. Jem Aswad, Variety, 15 Dec. 2023 Any reporter or gadfly worth their salt knew this was actually just a time for the board to call a department head onto the carpet and scream at them behind closed doors. Jaclyn Cosgrove, Los Angeles Times, 9 Dec. 2023 Best Picture Down Rustin The Netflix biopic, which starts its brief theatrical run this week, is being celebrated for Colman Domingo’s performance as the openly gay gadfly who organized the March on Washington. Vulture, 3 Nov. 2023 Around them buzzes a motley chorus of hapless government agents, spies, and literary gadflies like Frankenstein author Mary Shelley and Lord Byron, who in his attempts to defend the Luddites in the halls of power, spends a lot of time getting twisted up in his own poetry. WIRED, 22 Oct. 2023 The same went for Bill Maher, HBO’s late-night gadfly (and a WGA member). Mikey O'Connell, The Hollywood Reporter, 25 Sep. 2023 After Donald Trump had blasted open Clinton’s blue wall and swept Michigan, Wisconsin, and Pennsylvania, Sanders could no longer be dismissed as a relic or a gadfly. Ross Barkan, The New Republic, 3 Aug. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'gadfly.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


gad entry 1 + fly entry 4

First Known Use

1569, in the meaning defined at sense 1

Time Traveler
The first known use of gadfly was in 1569


Dictionary Entries Near gadfly

Cite this Entry

“Gadfly.” Dictionary, Merriam-Webster, Accessed 4 Mar. 2024.

Kids Definition


gad·​fly ˈgad-ˌflī How to pronounce gadfly (audio)
: any of various flies (as a horsefly or botfly) that are pests especially of livestock
: a person who annoys others especially by persistent criticism

Medical Definition


gad·​fly ˈgad-ˌflī How to pronounce gadfly (audio)
plural gadflies
: any of various flies (as a horsefly, botfly, or warble fly) that bite or annoy livestock

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