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

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

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

From BBC ● Aug. 7, 2026

She has proven a formidable adversary for Democrats for 30 years, most recently defeating a better-funded opponent in 2020 despite polls showing her trailing right up to election day.

From BBC ● Jul. 9, 2026

Noticing Carter’s frown, Archie decided to throw him a bone—Carter still ran the meetings and as Vigils president he could be a dangerous adversary.

From "The Chocolate War" by Robert Cormier

U.S. authorities are enforcing a new “Connected Vehicles” rule aiming to prevent foreign adversaries such as China and Russia from using technology such as data transmission and cameras in vehicles to spy on Americans.

From The Wall Street Journal ● Aug. 13, 2026

Finally, the U.S. needs to disperse facilities, such as naval and air bases, to make it more difficult for adversaries to attack.

From The Wall Street Journal ● Aug. 9, 2026

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

From Barron's ● Aug. 7, 2026

Iran's acting Defence Minister Majid Ibn al-Reza earlier said Tehran viewed every threat from its adversaries as "real and credible" even if it formed part of psychological warfare.

From BBC ● Aug. 3, 2026

They hurled themselves upon the enemy, sparrows and shrews siding them against their larger adversaries.

From "Redwall" by Brian Jacques

Related Words

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