Army vs Legions

When to use each in English, with meaning, register, and examples.

Army

Top 1,000 (very common)A2noun

Legions

Beyond 10,000 (less common)
Most common: Army
 ArmyLegions
Pronunciation🇬🇧 /["/ˈɑːmi/"]/🇺🇸 /["/ˈɑːrmi/"]/🇬🇧 //ˈliːdʒənz//🇺🇸 //ˈliːdʒənz//
MeaningA group of soldiers who are trained to fight.A large group of soldiers or people.
ExampleThe army defended the country against invasion.The ancient legions marched across the battlefield with great discipline.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Beyond 10,000 (less common)
CEFR levelA2-
Part of speechnoun
Collocationsgreat, huge, large, have, enter, go into, gather, advance, march, captain, chief of staff, colonel, in the army, great, huge, large, have, enter, go into, gather, advance, march, captain, chief of staff, colonel, in the army, vast, veritable, small, create, employ, hire, army oflegions of soldiers, legions of fans, legions of supporters
Antonymscivilian, non-militaryindividual, single, solitary
Common mistakesConfused with 'military', which is broader than just 'army'., Using 'army's' incorrectly as a verb instead of a noun., Mixing up singular and plural forms, e.g., saying 'armies' when referring to one.Confused with 'legion' as a singular noun., Used inappropriately in informal contexts., Misunderstood as only referring to soldiers.
Usage notesUse 'army' when talking about military forces. It is appropriate in formal contexts like discussions on defense or history, but may not be suitable in casual conversation about unrelated topics.Used in formal and historical contexts. Not common in everyday speech. Can imply many people in various situations.

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Army
Legions

Frequently asked questions: Army vs Legions

What's the difference between Army and Legions?

Army: A group of soldiers who are trained to fight. Legions: A large group of soldiers or people.

Which is more common: Army and Legions?

Army is the most common in everyday English.

Can you show an example of each?

Army: The army defended the country against invasion. Legions: The ancient legions marched across the battlefield with great discipline.

Can I use Army and Legions interchangeably?

Not always. Army and Legions are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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