foreign legion

American  

noun

1. a military unit consisting of foreign volunteers in the service of a state.

2. (initial capital letters) a specialized military unit of the French army, consisting of volunteers of all nationalities assigned to military operations and duties outside France.

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foreign legion British  

noun

1. a body of foreign volunteers serving in an army, esp that of France

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Etymology

Origin of foreign legion

An Americanism dating back to 1880–85

Example Sentences

Hayden Davies, a former British soldier who Russia has called a mercenary, was reportedly captured in Ukraine's Donbas region in late 2024 or early 2025 while serving with the country's foreign legion.

From BBC

“The Ukrainians just couldn’t keep up,” said one foreign legion soldier.

From New York Times

Taiwan has mandatory military service, which makes those who complete it eligible to join Ukraine's foreign legion.

From BBC

Also among the newly freed prisoners were two Americans who were members of Ukraine’s foreign legion, a group of foreign fighters who have taken part in some of the bloodiest battles in the war.

From New York Times

He said Mr Healy had no connection to the Ukraine military or any foreign legions and was in the country as a volunteer.

From BBC