army

noun

ar·​my ˈär-mē 

plural armies

1

a

: a large organized body of armed personnel trained for war especially on land

b

: a unit capable of independent action and consisting usually of a headquarters, two or more corps, and auxiliary troops

c

often Army : the complete military organization of a nation for land warfare

2

: a great multitude

an army of birds

3

: a body of persons organized to advance a cause

Synonyms of army

• battalion
• troops
• soldiers

Examples of army in a Sentence

the armies of Alexander the Great

He left home and joined the army after he graduated from high school.

The company employs an army of lawyers to handle its legal affairs.

They sent in a whole army of trained technicians.

The organization was founded by a dedicated army of volunteers.

Recent Examples on the Web

Many of these systems are already well-documented – from the country’s army of online censors maintaining its Great Firewall, to the surveillance cameras ubiquitous on almost every street and block across urban China. —Jessie Yeung, CNN Money, 4 Dec. 2025

Earlier this year, the Ukrainian army was sized at roughly 800,000 or more than 800,000 personnel for context, and this plan calls for it to be capped at 600,000. —Dana Taylor, USA Today, 4 Dec. 2025

The sensitive nature of Onoda’s army career ignited fury when the X post by Brighton’s academy department was shared on the Chinese social platform Weibo, an account popular with Premier League supporters in East Asia. —Andy Naylor, New York Times, 3 Dec. 2025

Our immune system functions as an army with soldiers working to detect and destroy invaders, said Walter Orenstein, a professor emeritus in the Emory School of Medicine. —The Washington Post, San Diego Union-Tribune, 2 Dec. 2025

Word History

Etymology

Middle English armee, armye "host of armed men, naval fleet, military expedition," borrowed from Anglo-French armé, armee, from armer "to arm entry 2" + -ee, suffix of action or result (going back to Vulgar Latin *-āta, noun derivative from feminine of Latin -ātus, past participle ending of Latin first-conjugation verbs)

Note: Compare Spanish armada "military force, fleet of warships"—see armada.

First Known Use

circa 1522, in the meaning defined at sense 1a

Phrases Containing army

• army ant
• general of the army
• sergeant major of the army
• standing army

Kids Definition

army

noun

ar·​my ˈär-mē 

plural armies

1

a

: a large body of men and women organized for land warfare

b

often capitalized : the complete military organization of a nation for land warfare

2

: a great number of persons or things

3

: a body of persons organized to promote an idea

Etymology

Middle English armee "army," from early French armee (same meaning), derived from Latin arma "weapons"