adversarial

adjective

ad·​ver·​sar·​i·​al ˌad-vər-ˈser-ē-əl How to pronounce adversarial (audio)
ˌad-və-, 
-ˈse-rē-
Synonyms of adversarial
: involving two people or two sides who oppose each other : of, relating to, or characteristic of an adversary or adversary procedures (see adversary entry 2 sense 2)
an adversarial relationship
an adversarial system of justice with prosecution and defense opposing each other

Synonyms of adversarial

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Examples of adversarial in a Sentence

an adversarial system of justice with prosecution and defense opposing each other the relationship between the president and the congress should not be adversarial if anything is to get done
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The Navy’s research aims to help ships maintain awareness of their cyber and physical operating conditions, dynamically adjust their defenses, and continue functioning during adversarial attacks. — Kaif Shaikh, Interesting Engineering, 29 Oct. 2026 With this election, Sanders and Warren have an opportunity to steer Democrats further left and turn that political influence into a legislative agenda that is more adversarial toward big business and the private sector. — David Sivak, The Washington Examiner, 28 Oct. 2026 Hynes has said his relationship with the board — a quasi-judicial, three-member board that hears appeals to the assessor’s valuations — would be less adversarial than Kaegi’s. — A.d. Quig, Chicago Tribune, 27 Oct. 2026 The original model for the kind of adversarial speech the First Amendment aims to protect, McGrane said, was the speech American colonists used against the British. — Sarah Cutler, Idaho Statesman, 15 Oct. 2026 See All Example Sentences for adversarial

Word History

Etymology

adversary entry 1 + -al entry 1

First Known Use

1839, in the meaning defined above

Time Traveler
The first known use of adversarial was in 1839

Rhymes for adversarial

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Browse Nearby Words

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Cite this Entry

“Adversarial.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/adversarial. Accessed 31 Oct. 2026.

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Kids Definition

adversarial

adjective
ad·​ver·​sar·​i·​al ˌad-vər-ˈser-ē-əl How to pronounce adversarial (audio)
: involving two people or two sides who oppose each other

Legal Definition

adversarial

adjective
ad·​ver·​sar·​i·​al ˌad-vər-ˈser-ē-əl How to pronounce adversarial (audio)
: of, relating to, or characteristic of an adversary or adversary procedures : adversary
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