A legion is a horde or a large number of people or things. It was originally a term for a military unit.

In Roman times, a legion was a large unit of men in the army, and the word is still used in many militaries. However, it also means a whole bunch of people doing anything. If someone has many fans, you can say legion of fans or legions of fans, but either way, that's a lot of fans. There are legions of stars in the sky. When you see legion, you can be sure there's an awful lot of something.

Definitions of legion
  1. noun
    a large military unit
    “the French Foreign Legion
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    foreign legion
    a military unit composed of foreign volunteers who serve the state
    French Foreign Legion
    a former foreign legion in the French army that was used for military duties outside of France
    type of:
    force, military force, military group, military unit
    a unit that is part of some military service
  2. noun
    association of ex-servicemen
    “the American Legion
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    type of:
    a formal organization of people or groups of people
  3. noun
    archaic terms for army
    synonyms: host
    see moresee less
    Roman Legion
    a division of from 3000 to 6000 men (including cavalry) in the Roman army
    (plural) hosts or armies; used in the book of Romans in the New Testament
    type of:
    army, ground forces, regular army
    a permanent organization of the military land forces of a nation or state
  4. noun
    a vast multitude
    synonyms: horde, host
    see moresee less
    type of:
    concourse, multitude, throng
    a large gathering of people
  5. adjective
    amounting to a large indefinite number
    “Palomar's fans are legion
    synonyms: numerous
    a quantifier that can be used with count nouns and is often preceded by `as' or `too' or `so' or `that'; amounting to a large but indefinite number
Word Family

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