adversary

American  

[ad-ver-ser-ee] / ˈæd vərˌsɛr i /

noun

• adversaries
  plural

1. a person, group, or force that opposes or attacks; opponent; enemy; foe.

   Antonyms:

   ally

2. a person, group, etc., that is an opponent in a contest; contestant.

3. the Adversary, the devil; Satan.

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adjective

1. of or relating to an adversary.

2. involving adversaries, as plaintiff and defendant in a legal proceeding.

   an adversary trial.

adversary British  

/ ˈædvəsərɪ /

noun

1. a person or group that is hostile to someone; enemy

2. an opposing contestant in a game or sport

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adjective

1. the US term for adversarial

Synonym Usage

Adversary, antagonist mean a person or a group contending against another. Adversary suggests an enemy who fights determinedly, continuously, and relentlessly: a formidable adversary. Antagonist suggests one who, in hostile spirit, opposes another, often in a particular contest or struggle: a duel with an antagonist.

Other Word Forms

Derived Forms

• adversariness
  noun
• adversarial
  adjective
• nonadversarial
  adjective

Inflected Forms

Nouns

• adversaries
  plural

Etymology

Origin of adversary

First recorded in 1300–50; Middle English adversarie, from Latin adversārius; equivalent to adverse + -ary; replacing Middle English adversere, from Anglo-French

Explanation

An adversary is an enemy or someone who opposes someone else. In tennis, you stand across the net from your adversary. Adversary is related to the word adverse, meaning "against or contrary" — so think of an adversary as someone whom you are fighting against. If you're the undefeated chess champion, you have bested every single one of your adversaries. Adversary is derived from a Latin word meaning "against."

Example Sentences

See Examples For:

adversary adversaries

For decades he was Washington’s most tenacious adversary.

From The Wall Street Journal ● Aug. 13, 2026

"When the president travels to war zones, there are frequently tactics and techniques used to create doubt in an adversary of which aircraft or which movement that he's going to make," he added.

From BBC ● Aug. 11, 2026

Iran has a clear geopolitical motive and a history of targeting the water sector, and the fact that the attacks were readily detected makes a stealthier adversary like China less likely, Kaiser said.

From The Wall Street Journal ● Aug. 8, 2026

The Strait of Hormuz is, by some accounts, named for a Zoroastrian deity destined to emerge victorious after a 9,000-year standoff with an adversary.

From Los Angeles Times ● Aug. 8, 2026

I felt I was dealing fate a serious blow by engaging such a handsome adversary.

From "Life of Pi" by Yann Martel

She is right that open-weight models developed by adversaries shouldn’t be used in intelligence systems, military networks or critical infrastructure.

From The Wall Street Journal ● Aug. 11, 2026

The researchers also monitor to ensure satellite operators are complying with their licences and track foreign "adversaries".

From Barron's ● Aug. 7, 2026

About the 10th or 12th time Spidey defeats a gaggle of adversaries by wrapping them up in webs, this series seems entangled in its own predictability.

From The Wall Street Journal ● Jul. 30, 2026

"If you look at what our adversaries are building, they're also building significantly large platforms - aircraft, ships, submarines. And they're supplemented by some of these unmanned capabilities."

From BBC ● Jul. 23, 2026

“I know we’ve been adversaries in the past...but a little bit of goodwill on both our parts can go a long way.”

From "Dry" by Neal Shusterman and Jarrod Shusterman

Related Words

• antagonist
• attacker
• competitor
• enemy
• foe
• opponent
• rival