gad·​fly | \ ˈgad-ˌflī How to pronounce gadfly (audio) \

Definition of gadfly

1 : any of various flies (such as a horsefly, botfly, or warble fly) that bite or annoy livestock
2 : a person who stimulates or annoys other people especially by persistent criticism a political gadfly

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

a loud sports commentator who was a tactless gadfly during post-game interviews with the losing team
Recent Examples on the Web She was aided by the maverick campaign of ultranationalist gadfly Eric Zemmour, whose snarling anti-immigrant, anti-establishment rhetoric has made Le Pen — a far-right mainstay for years — look comparatively moderate. Washington Post, 7 Apr. 2022 Well, Ishmael, in making that statement, fulfills his obligation as a satirist, as a gadfly, as the court jester. David Remnick, The New Yorker, 19 Feb. 2022 Portuguese gadfly Bruno Maceas declared John Mearsheimer, the famous advocate for foreign-policy realism, who predicted this conflict rather presciently eight years ago, to have lost his credibility and reputation. Michael Brendan Dougherty, National Review, 16 Mar. 2022 Consider this year’s New York City mayoral race, whose foregone Democratic conclusion left a void in the Republican primary, which was filled by the gadfly Guardian Angel Curtis Sliwa. Ian Crouch, The New Yorker, 2 Dec. 2021 Coe, an autodidact and the son of the outlaw-country musician David Allan Coe, relishes his role as scholar-enthusiast-gadfly, and his zeal is the show’s animating force. Sarah Larson, The New Yorker, 13 Dec. 2021 All evidence suggests that the Biden administration has accepted Mr. Summers’s role as unofficial economics whisperer and frequent gadfly. New York Times, 25 June 2021 McLeod, a right-wing gadfly who has twice run for San Antonio mayor, was looking to provoke. Gilbert Garcia, San Antonio Express-News, 20 Jan. 2022 The journal is also a candid record of the homosexual underground in mid-century New York City, and the memoirs of a young gadfly’s encounters with such figures as Marcel Duchamp, Alice B. Toklas, and Gore Vidal. Benjamin Anastas, The New Yorker, 1 Nov. 2021 See More

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

First Known Use of gadfly

1569, in the meaning defined at sense 1

History and Etymology for gadfly

gad entry 1 + fly entry 4

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Last Updated

9 May 2022

Cite this Entry

“Gadfly.” Dictionary, Merriam-Webster, Accessed 17 May. 2022.

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More Definitions for gadfly


gad·​fly | \ ˈgad-ˌflī How to pronounce gadfly (audio) \
plural gadflies

Kids Definition of gadfly

1 : a large biting fly
2 : a person who annoys others especially with constant criticism


gad·​fly | \ ˈgad-ˌflī How to pronounce gadfly (audio) \
plural gadflies

Medical Definition of gadfly

: any of various flies (as a horsefly, botfly, or warble fly) that bite or annoy livestock

More from Merriam-Webster on gadfly

Nglish: Translation of gadfly for Spanish Speakers


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