le·​gion | \ ˈlē-jən How to pronounce legion (audio) \

Definition of legion

 (Entry 1 of 2)

1 : the principal unit of the Roman army comprising 3000 to 6000 foot soldiers with cavalry Caesar and his legions defeated the Gauls.
2 : a large military force especially : army sense 1a the French Foreign Legion
3 : a very large number : multitude won him … a legion of devoted followers— Irving Kolodin
4 : a national association of ex-servicemen the American Legion



Definition of legion (Entry 2 of 2)

: many, numerous the problems are legion

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Synonyms & Antonyms for legion

Synonyms: Noun

Synonyms: Adjective

Antonyms: Adjective

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Examples of legion in a Sentence

Noun Legions of people came to see him perform. joined the French Foreign Legion Adjective the obstacles that the programmers had to overcome have been legion
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Recent Examples on the Web: Noun More significant, though, Boeing landed 30 firm orders for its embattled 737 MAX, which remains grounded around the globe while legions of regulators scrutinize the airplane's safety. Dan Catchpole, Fortune, "Boeing 737 MAX Gets a $1.2 Billion Vote of Confidence at the Dubai Air Show," 20 Nov. 2019 Despite its philanthropic efforts, Google’s critics remain legion — even within the tech universe. Washington Post, "AP Interview: Google VP worries about online content, too," 19 Nov. 2019 Those supporters were, at one time, legion: few men have had so many friends to lose, and few have done so as efficiently. Casey Cep, The New Yorker, "The Legacy of a Radical Black Newspaperman," 18 Nov. 2019 The left, which is legion within university faculties and student bodies, hates Trump. John Kass, chicagotribune.com, "Column: Northwestern University, the cancel culture and ‘Whatsoever things are true’," 15 Nov. 2019 Having one or two legions always on the move often meant that most others could stay in their barracks. Victor Davis Hanson, National Review, "The Trump Doctrine: Deterrence without Intervention?," 5 Nov. 2019 There’s the Onewheel, and an ever-improving legion of e-bikes. Alexander George, Popular Mechanics, "This Swedish Electric Moped Is Also a Mobile Generator," 5 Nov. 2019 Since the Coleman report, legions of researchers have tried to tease out exactly what was going on and whether the seemingly obvious link between school funding and student performance could be proved. Karl W. Smith, Twin Cities, "Karl W. Smith: Warren won’t improve schools by limiting choice," 27 Oct. 2019 There are hundreds of web sites, legions of online communities, and whole books devoted to perpetuating these claims. Scott W. Stern, The New Republic, "The Making of a White Supremacist Myth," 24 Oct. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'legion.' 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 legion


13th century, in the meaning defined at sense 1


1687, in the meaning defined above

History and Etymology for legion

Noun and Adjective

Middle English, from Anglo-French, from Latin legion-, legio, from legere to gather — more at legend

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Time Traveler for legion

Time Traveler

The first known use of legion was in the 13th century

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Statistics for legion

Last Updated

26 Nov 2019

Cite this Entry

“Legion.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/legions. Accessed 5 December 2019.

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More Definitions for legion


How to pronounce legion (audio)

English Language Learners Definition of legion

 (Entry 1 of 2)

: a large group of soldiers in ancient Rome
: a large group of soldiers
: a national organization for former soldiers



English Language Learners Definition of legion (Entry 2 of 2)

: very many or numerous


le·​gion | \ ˈlē-jən How to pronounce legion (audio) \

Kids Definition of legion

1 : a group of from 3000 to 6000 soldiers that made up the chief army unit in ancient Rome
3 : a very great number She has a legion of admirers.

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