legion

1 of 2

noun

le·​gion ˈlē-jən 

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

legion

2 of 2

adjective

: many, numerous

the problems are legion

Synonyms of legion

Noun

• army

Adjective

• many
• numerous
• multiple

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

Recent Examples on the Web

Noun

People walked through the legions of resting workers, asking if anyone needed a ride home. — Devin Friedman, Rolling Stone, 11 Sep. 2026

Among the newspaper’s alums was Mildred Wirt Benson, better known to legions of Nancy Drew fans as Carolyn Keene, the original author of the mystery books featuring the plucky amateur detective. — Kate Brumback, Fortune, 10 Sep. 2026

The results are notable as a legion of drugmakers — including Pfizer, Genentech, GSK, and AstraZeneca — previously tried and failed to use OX40 as a weapon against tumors over the past 15 years. — Jason Mast, STAT, 8 Sep. 2026

La Jolla Whether by sea, by air or by upscale shopping street, La Jolla is likely to grab you, especially in fall after the summer tourist legions have retreated. — Los Angeles Times, 8 Sep. 2026

Word History

Etymology

Noun and Adjective

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

First Known Use

Noun

13th century, in the meaning defined at sense 1

Adjective

1687, in the meaning defined above

Rhymes for legion

• region
• collegian
• norwegian
• subregion

Kids Definition

legion

noun

le·​gion

ˈlē-jən

1

: the chief unit of the Roman army consisting of 3000 to 6000 foot soldiers with cavalry

2

: army sense 1a

3

: a very large number : multitude