armor

American  

[ahr-mer] / ˈɑr mər /

especially British, armour

noun

1. any covering worn as a defense against weapons.

2. a suit of armor.

3. a metallic sheathing or protective covering, especially metal plates, used on warships, armored vehicles, airplanes, and fortifications.

4. mechanized units of military forces, as armored divisions.

5. Also called armament.  any protective covering, as on certain animals, insects, or plants.

6. any quality, characteristic, situation, or thing that serves as protection.

   A chilling courtesy was his only armor.

7. the outer, protective wrapping of metal, usually fine, braided steel wires, on a cable.

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verb (used with object)

1. to cover or equip with armor or armor plate.

armor British  

/ ˈɑːmə /

noun

1. the US spelling of armour

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armor Idioms  

1. see chink in one's armor; knight in shining armor.

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Other Word Forms

• antiarmor adjective
• armorless adjective
• subarmor noun

Etymology

Origin of armor

1250–1300; Middle English armo ( u ) r, armure < Anglo-French armour ( e ), armure Old French armëure < Latin armātūra armature; assimilated, in Middle English and Anglo-French, to nouns ending in -our -or ²

Explanation

The metal suit worn by knights as protection in battle is called armor. You can still see suits of armor in many museums today. These days, soldiers still use armor to protect them from bullets and other weapons, though it's not usually made of metal. Modern armor, like bullet-proof vests, is made of extremely strong, dense fabric, while 13th century armor was typically made of steel. In the 14th century, the word itself meant "defensive covering worn in combat" and "means of protection," from the Old French armeure, "weapons or armor," with its Latin root, arma, "arms or gear."

Example Sentences

Tigri, grim-faced in body armor, stood next to Samary, slightly comical with his helmet askew and rifle hanging from a sling.

From The Wall Street Journal • Mar. 12, 2026

Because producing it requires nitrogen and other minerals, thicker armor represents a larger resource investment for each individual ant.

From Science Daily • Mar. 10, 2026

For those fascinated by samurai military feats, armor and weapons abound, especially in the first section, where superb examples trace various adaptations to changing modes of warfare and armor’s use as a diplomatic gift.

From The Wall Street Journal • Mar. 7, 2026

I was wearing my best armor: a black dress that accentuated my curves, a striped bolero to cover the arms I’ve resented for years and black platform sandals displaying ruby toes.

From Los Angeles Times • Feb. 27, 2026

It was wearing a shredded rubakha, dingy and rusty and matted to the thing’s body with some kind of metallic bands like frail armor.

From Anya and the Nightingale by Sofiya Pasternack

Related Words

• bulletproof vest
• shield