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

army, array, battalion, host

Synonyms: Adjective

beaucoup [slang], many, multifold, multiple, multiplex, multitudinous, numerous

Antonyms: Adjective


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Examples of legion in a Sentence


Legions of people came to see him perform. joined the French Foreign Legion


the obstacles that the programmers had to overcome have been legion
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Recent Examples on the Web: Noun

In Regina George fashion, she's introduced by legions of admirers from North Shore High—including the original Aaron Samuels, Jonathan Bennett—talking about their devotion to the pop star. Halie Lesavage, Glamour, "Every Single Movie Reference in Ariana Grande's 'Thank U, Next' Music Video," 30 Nov. 2018 Their quest is one shared by the legions of traders, techies, online scribblers, and gamblers and grifters mesmerized by Bitcoin. Lionel Laurent, Bloomberg.com, "What Bitcoin Is Really Worth May No Longer Be Such a Mystery," 19 Apr. 2018 Its destruction by Titus’s legions led to the fall of the Judean state and its priesthood—and to the rebuilding of Judaism. Dominic Green, WSJ, "‘A History of Judaism’ Review: The Book of Books," 30 Mar. 2018 Around this northern Indian city and in similar regions across the country, legions of young Indians struggle to survive in the... Bill Spindle, WSJ, "‘The Youth Bulge’: India Struggles to Employ an Exploding Population," 22 Apr. 2019 Heinrich, the Democrat, recently threw his support behind legalizing marijuana, while Johnson already is contemplating how to provide pardons for legions of drug-possession convicts. Morgan Lee, The Seattle Times, "Libertarian says Trump, Democrats need a swing-vote senator," 9 Oct. 2018 Reissues of ’90s records are legion right now, but this is not one to feel cynical about. Taylor Antrim, Vogue, "Talking to Rebecca Gates of the Spinanes, as Manos—a Lost ’90s Indie Rock Classic—Gets a Deluxe Reissue," 5 Dec. 2018 Invisible to the crowds flocking to World Cup venues all over Russia are legions of migrant workers from Central Asia, who built the stadiums and keep them running, staff concession stands, and clean up after fans who revel through city streets. Kevin Baxter, latimes.com, "Migrant workers got World Cup started and have kept it going," 9 July 2018 And no country’s wartime record is more muddled than Germany’s, whose arms and armies have attracted legions of devoted fans. Kyle Mizokami, Popular Mechanics, "Was the Famous German Tiger Tank Really That Great?," 20 Dec. 2018

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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Dictionary Entries near legion






legionary ant


Statistics for legion

Last Updated

14 May 2019

Look-up Popularity

Time Traveler for legion

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

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More Definitions for legion



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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More from Merriam-Webster on legion

Rhyming Dictionary: Words that rhyme with legion

Thesaurus: All synonyms and antonyms for legion

Spanish Central: Translation of legion

Nglish: Translation of legion for Spanish Speakers

Britannica English: Translation of legion for Arabic Speakers

Britannica.com: Encyclopedia article about legion

Comments on legion

What made you want to look up legion? Please tell us where you read or heard it (including the quote, if possible).


highly pertinent or appropriate

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