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

But Rubel and her legion of supporters were prepared for such a setback. Britni De La Cretaz, Longreads, "Flagrant Foul: Benching Teen Moms Before Title IX," 14 Aug. 2019 Sue Gordon was a name Americans were never supposed to know—the exemplar par excellence of the legion of career, nonpartisan officials who devote a lifetime to anonymous government service. Garrett M. Graff, WIRED, "Trump’s Intel Vacancies Put Americans in Danger," 9 Aug. 2019 The opportunities for buying influence this throws up would be legion even if a Democratic administration reformed campaign-finance laws. The Economist, "The Kochtopus’s garden," 29 Aug. 2019 Celebrities like Jay-Z, Kevin Hart, and Philadelphia 76ers owner Michael G. Rubin, as well as legions of fans, voiced their support for the rapper with the #FreeMeekMill movement. Christian Holub, EW.com, "Meek Mill pleads guilty to misdemeanor charge, won't serve additional prison time," 27 Aug. 2019 Roman legions invade Colorado Viejo San Acacio The 1856 Capilla de Viejo San Acacio is named for St. Acacio, a Roman soldier who converted to Christianity. Tom Noel, The Know, "16 strange, spooky and (mostly) true Colorado stories to tell around a campfire," 24 Aug. 2019 The tweet has since amassed 2,000 likes and legions of comments from fans welcoming her back to the Twittersphere. Kaleigh Fasanella, Allure, "Jaclyn Hill Just Got Back on Social Media, and There’s Already Backlash," 22 Aug. 2019 From a recruitment perspective, selling programs with six-figure price tags may well be impossible without legions of counselors enticing prospects through each step of the enrollment process. Katerina Manoff, The Atlantic, "How They (Online Graduate Programs) Get You," 14 Aug. 2019 Tumblr, the social network used by Taylor Swift and legions of pop culture fans, has been sold by its owner Verizon to the blogging platform WordPress. Patrick Smith, NBC News, "Jeffrey Epstein sex trafficking investigation goes on: Read the Morning Rundown," 13 Aug. 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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Dictionary Entries near legion






legionary ant


Statistics for legion

Last Updated

17 Sep 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).


authorized for issue (as a bond)

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