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

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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

a loud sports commentator who was a tactless gadfly during post-game interviews with the losing team

Recent Examples on the Web

When not inveighing against Islam and immigrants, ultranationalist gadfly and former Trump adviser Stephen K. Bannon is working to revive the Committee on the Present Danger, a hawkish Soviet-era group now recast for a confrontation with China. Ishaan Tharoor, Washington Post, "Hong Kong’s protests flare in the shadow of the U.S.-China rivalry," 29 July 2019 Greenberg seems increasingly isolated, an aging gadfly whose moral rigidity and cynicism have alienated his colleagues. Rachel Poser, Harper's magazine, "Common Ground," 19 Aug. 2019 Present at the event was medical gadfly Robert F. Kennedy Jr., who has been campaigning against vaccines on the basis of false science since 2005. Time, "'They’re Chipping Away.' Inside the Grassroots Effort to Fight Mandatory Vaccines," 13 June 2019 So the gadfly part of it was that there really weren’t ... Eric Johnson, Vox, "The problem with tech people who want to solve problems," 26 June 2019 One of the few journalists to note the existence of the UMG archive was Nikki Finke, the entertainment-industry blogger and gadfly. New York Times, "The Day the Music Burned," 11 June 2019 As time and circumstance changed, Mr. Sanders gradually evolved from a marginalized gadfly in the House to a reliable Democratic vote in the most insider-y club in Washington, the United States Senate. Glenn Thrush, New York Times, "Outsider or Insider? How Bernie Sanders Learned to Walk the Line," 6 July 2019 Sanders’s ideology is the product of the winding circumstances of his long career, tracing an unlikely trajectory from radical New England gadfly to U.S. senator. Matthew Zeitlin, The New Republic, "Bernie’s Red Vermont," 13 June 2019 However, Judge Richard Leon of the U.S. District Court for the District of Columbia has become something of a gadfly for the firms. Sy Mukherjee, Fortune, "A Holdout on the CVS-Aetna Deal: Brainstorm Health," 4 June 2019

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.

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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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Statistics for gadfly

Last Updated

20 Sep 2019

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Time Traveler for gadfly

The first known use of gadfly was in 1569

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Financial Definition of gadfly

What It Is

A gadfly is a shareholder who publicly criticizes a company's executives at the annual shareholders meeting.

How It Works

The term gets its name from the insect, which bites and annoys animals (usually livestock).

There are many famous gadflies, but one of the most notable was Evelyn Y. Davis, who spent 40 years confronting managers at annual meetings regarding their compensation and performance. Sometimes she wore costumes and bathing suits in the meetings to get attention. In one instance, she badgered the board of Bristol-Myers Squibb to change its corporate charter to require annual elections for all board members. She was able to get Dow Jones and a real estate firm to follow suit as well. In 2003, she made more than 50 proposals at various companies, including (but not limited to) AT&T, DuPont, Ford, and JPMorgan.

Why It Matters

Gadflies are annoying to management, but they are useful to the rest of us. They often draw attention to problems that others may have overlooked, and they can encourage action from other shareholders. Their courage to stand up and dissent is notable if not entertaining at times.

Source: Investing Answers



English Language Learners Definition of gadfly

: someone who annoys people by being very critical


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

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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

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More from Merriam-Webster on gadfly

Rhyming Dictionary: Words that rhyme with gadfly

Thesaurus: All synonyms and antonyms for gadfly

Spanish Central: Translation of gadfly

Nglish: Translation of gadfly for Spanish Speakers

Comments on gadfly

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miscellaneous remnants or debris

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