gad·​fly | \ˈgad-ˌflī \

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

There’s kind of schmoozing and being known and being a gadfly. Eric Johnson, Recode, "How to get a job in venture capital," 26 Aug. 2018 To recap, there were three candidates: the current president, Kirsan Nikolayevich Ilyumzhinov, the current deputy president, Georgios Makropoulos, and English GM and Twitter gadfly Nigel Short. Chris Chase,, "Chess notes," 7 July 2018 Another time, she was sued for defamation by a local political gadfly who has been convicted of witness intimidation and threatening to shoot a city employee. Michael Levenson,, "Fears of violence unsettle newsrooms," 29 June 2018 In January 2008, Wyandotte County political gadfly T.J. Reardon filed a petition to summon a grand jury investigation into the Board of Public Utilities and allegations of misappropriation of funds and awarding no-bid contracts. Bryan Lowry And Steve Vockrodt, kansascity, "Kobach can be investigated by citizen grand jury, Kansas Court of Appeals rules," 8 June 2018 And in a state of nearly 40 million people, her 11 Republican challengers are a mix of oddballs, gadflies, and earnest but superficial candidates. NBC News, "California's GOP is collapsing. Is that a sign for Republicans nationwide?," 4 June 2018 Then there is a whole second tier to consider, including billionaire gadfly Tom Steyer, who is using his resources to assemble a mighty list by enticing Democrats to sign some symbolic petition about impeachment. Chris Stirewalt, Fox News, "Dems start to get serious about 2020," 1 June 2018 That is reasonable, says Antonio Garcia-Martinez, a former Facebook ad-targeting product manager and current Facebook gadfly. Christopher Mims, WSJ, "What Mark Zuckerberg Didn’t Say About What Facebook Knows About You," 14 Apr. 2018 Unfortunately, our deal was undone thanks to Republican Danny Tarkanian, a perpetual candidate and racist gadfly running in Nevada’s 3rd Congressional District against Democrat Susie Lee. Jason Johnson, The Root, "Kanye West Invades the Nevada Congressional Race, and Now I’m Forced to Write About Him," 9 May 2018

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

1593, 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

15 Nov 2018

Look-up Popularity

Time Traveler for gadfly

The first known use of gadfly was in 1593

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More Definitions for gadfly



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 \
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 \
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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living or existing for a long time

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