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

Corporate zombies, unable to generate the cash to pay off their debts, are legion. Edward Chancellor, WSJ, "‘Red Flags’ Review: Trade War and Other Troubles," 9 Dec. 2018 The waves of firings spawned a legion of disaffected former employees who congregate online to air their grievances and swap stories. Gerrit De Vynck, The Seattle Times, "‘Pit-bull’ lawyer suing IBM for age discrimination," 17 Sep. 2018 The finale left the show with more questions than answers, and legions of disappointed fans expecting better of a series that spent so much time dwelling on detail and nuance its first six seasons. Julie Kosin, Harper's BAZAAR, "The Game of Thrones Finale Is Filled with Plot Holes and Twitter Is Calling Them All Out," 20 May 2019 The masked animal did so by scaling a St. Paul, Minn., skyscraper, a la Spider-Man, and in the process riveting — and terrifying — legions of humans who followed online. Karin Brulliard, Washington Post, "A raccoon is scaling the side of a tall skyscraper, and it’s incredibly stressful," 12 June 2018 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

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

11 Jun 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

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