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

This drone realism is notable because a perennial Washington complaint is that the island buys too many big platforms like fighter jets and isn’t focused enough on an “asymmetric” defense against a larger adversary.

From The Wall Street Journal ● Aug. 31, 2026

"You hint to the adversary that you might cause a really big problem: that tomorrow might be more serious."

From BBC ● Aug. 7, 2026

Here as well, the California Public Employment Relations Board joined the case on appeal as the district’s primary adversary before the appellate and state supreme court.

From The Wall Street Journal ● Aug. 6, 2026

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

To defeat an adversary who was your equal, maybe even your superior, it wasn’t necessarily enough just to give your all from start to finish.

From "The Boys in the Boat: Nine Americans and Their Epic Quest for Gold at the 1936 Berlin Olympics" by Daniel James Brown

"I believe that only then will we be able to begin to heal and move forward -- not as adversaries, but as human beings and as peoples equal in dignity."

From Barron's ● Aug. 28, 2026

What follows is an electric encounter between adversaries, and actors.

From The Wall Street Journal ● Aug. 28, 2026

The MoD said it would not comment on specific security procedures as this could benefit potential adversaries, but it said the security of defence assets was a top priority for the Labour government.

From BBC ● Aug. 27, 2026

But the West has misjudged adversaries before, and Mr. Putin may have his own calculations that look different from inside the Kremlin.

From The Wall Street Journal ● Aug. 27, 2026

The opening section of his speech also goes on the attack, fulfilling Ad Herennium’s rather gleeful injunction to use this section to “make our adversaries unpopular.”

From "Words Like Loaded Pistols" by Sam Leith

Related Words

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