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

There’s a comic trope beloved by playwrights, novelists and screenwriters about the fighters all suited up for battle, only to discover that their adversary refuses to play.

From Los Angeles Times ● Jul. 30, 2026

Might she get in front of a news camera, or on a debate stage, and bungle so badly that an adversary features her in an ad?

From The Wall Street Journal ● Jul. 29, 2026

But even with the new investment it is likely that an adversary armed with hypersonic missiles would be able to overwhelm Britain's defences.

From BBC ● Jun. 30, 2026

The trickiest tool is export controls, or restricting cutting-edge technology, like advanced AI chips, from reaching an adversary.

From The Wall Street Journal ● Jun. 23, 2026

For the first time in the Cold War, American military leaders felt that they had a clear image of Russia's military capabilities—knowledge that would help the United States stay one step ahead of its adversary.

From "Spies: The Secret Showdown Between America and Russia" by Marc Favreau

It’s not paranoid to worry that adversaries could exploit these systems.

From The Wall Street Journal ● Jul. 26, 2026

Officials said the increase was being driven by a mix of online threats, lone actors, ideological extremism, foreign adversaries and individuals experiencing mental health crises.

From BBC ● Jul. 23, 2026

Critical investments were needed to prevent adversaries from outpacing the US, he continued.

From BBC ● Jul. 22, 2026

“It is critical that we stay ahead of our adversaries and we must have the funds before we are out of time,” Caine said.

From Los Angeles Times ● Jul. 21, 2026

They were paired intentionally, doomed to be adversaries.

From "Scythe" by Neal Shusterman

Related Words

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