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ad·​ver·​sary ˈad-vər-ˌser-ē How to pronounce adversary (audio)
plural adversaries
: one that contends with, opposes, or resists : an enemy or opponent
a clever adversary
adversariness noun


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: of, relating to, or involving an enemy or adversary
: having or involving antagonistic parties or opposing interests
Divorce can be an adversary proceeding.

Did you know?

Adversary comes from Latin advertere, meaning "to turn toward." The vertere of advertere means "to turn" and is the source of a number of English words. Along with obvious derivatives like inadvertent and adverse are some surprises, including anniversary, vertebra, and prose (this last coming by way of a Latin contraction of a form of the verb provertere, meaning "to turn forward").

Example Sentences

Noun He's a very smart criminal who pushes emotional buttons to get what he wants. He's quite a worthy adversary for Mac and the team. TV Guide, 2-8 June 2008
American diplomacy after World War II exemplified the soundness of this principle. We put our power at the disposal of all who cherished freedom and peace. We did things for others they couldn't do for themselves. We defended others, yes, but we also forgave our former enemies and helped reconcile old adversaries, such as France and Germany. Colin L. Powell, Wilson Quarterly, Summer 2004
Nike's adversary was an amorphous group of disgruntled consumers connected by a decentralized network of e-mail addresses. Although the press has presented my battle with Nike as a David versus Goliath parable, the real story is the battle between a company like Nike, with access to the mass media, and a network of citizens on the Internet … Jonah Peretti, Nation, 9 Apr. 2001
Not perfected until the eve of World War I, this small boat cruised on the surface with a diesel engine that also charged the batteries that powered the submarine's electric motors for submerged operation. If it spotted an adversary, the submarine would dive, either to escape or attack. Archer Jones, Elements of Military Strategy, 1996
His political adversaries tried to prevent him from winning the nomination. our old cat seemed to consider the new kitten an adversary Adjective The quest for air superiority would come to include strikes on adversary airfields, but only as part of a larger effort also involving such staples as defensive fighter interception, offensive air sweeps, and escort missions with bombers designed to draw enemy fighters into battle. John Prados, MHQ : The Quarterly Journal of Military History, Spring 1996
Critics of military justice complain that it is not a true adversary system because the JAG has authority over judges, prosecutors and defense attorneys and controls the funds of each. Fred Strasser, National Law Journal, 4 Mar. 1991
there was a long history of adversary dealings between the two nations See More
Recent Examples on the Web
The bill would limit the operation of foreign cranes used at U.S. ports that are made by U.S. adversaries—such as China. Brooke Singman, Fox News, 10 May 2023 Director of National Intelligence Avril Haines testified last week that U.S. adversaries like China and Russia could seize on a default, and economists have painted a grim picture for Americans’ pocketbooks if the U.S. were unable to pay bondholders and other bills. Alexandra Hutzler, ABC News, 8 May 2023 The foreign adversaries listed in the bill include China, Cuba, Iran, North Korea, Russia and Venezuela. Sudiksha Kochi, USA TODAY, 4 May 2023 So, what can be done to mitigate the risks associated with the use of generative AI by cyber adversaries? Matthew Morgan, Forbes, 3 May 2023 The groundhog, as New England gardeners have known for time immemorial, is a formidable adversary., 3 May 2023 Advertisement The fallout has endured for weeks after the classified files exposed how the United States gathers intelligence on its allies and adversaries; documentation of battlefield conditions in Ukraine; movements of foreign leaders; and other revelations. Kelsey Ables, Washington Post, 28 Apr. 2023 There were so many adversaries and forces that Franklin was facing this season (the CIA, his family, the KGB) and there was so much double-crossing and various motives. Hilary Lewis, The Hollywood Reporter, 20 Apr. 2023 Incumbents must radically shift their mindset recasting transformers as strategic allies instead of adversaries. François Candelon, Fortune, 7 Apr. 2023
Such sensitive information, along with financial information and private messages, is helpful for adversary intelligence agencies to use as leverage for blackmail or coercion. Dan Morse, Alex Horton, Anchorage Daily News, 30 Sep. 2022 Kennedy shows similar backpedaling when discussing his complicated relationship with Derrick Bell, a former Harvard Law professor and pioneer of critical race theory, whom Kennedy considered a mentor, friend and — perhaps most notably — adversary. Washington Post, 10 Sep. 2021 Jarman faces the ultimate, inevitable adversary head on. The Economist, 23 May 2020 Kristen Wiig will star as famous Wonder Woman adversary Cheetah, while The Mandalorian‘s Pedro Pascal will play comic book villain Maxwell Lord. Nick Romano,, 9 Dec. 2019 In the story's boldest stroke of gallows humor, Joe and a fallen adversary croon softly together to a song on the radio, two souls improbably united by the strange, terrible intimacy of professional murder. Justin Chang,, 5 Apr. 2018 At the same time, Trump's tirades against trade deals with nations like China played into a belief among many people that such pacts had hollowed out the American dream, while building middle classes lives for citizens of adversary nations. Stephen Collinson, CNN, 28 Sep. 2017 In oral arguments via telephone Tuesday, a panel of three appellate judges pressed both Purcell and adversary August Flentje, special counsel to the assistant U.S. attorney general, for additional evidence to back up their claims. Marisa Kendall, The Mercury News, 9 Feb. 2017 The measure would bar the Pentagon from buying satellite services if there is a threat that they could be compromised by cyber vulnerabilities or because they are launched by or contained parts from adversary nations. John M. Donnelly, The Seattle Times, 20 June 2017 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'adversary.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History



Middle English, borrowed from Anglo-French & Latin; Middle English adversaire, adversarie, borrowed from Anglo-French adverser, adverserie, borrowed from Latin adversārius, noun derivative from adversārius "opposed (to), inimical, adverse," from adversus "turned toward, facing" + -ārius -ary entry 2 — more at adverse


earlier, "opposed, antagonistic," going back to Middle English adversarie, borrowed from Anglo-French & Latin; Anglo-French, borrowed from Latin adversārius — more at adversary entry 1

First Known Use


14th century, in the meaning defined above


14th century, in the meaning defined at sense 1

Time Traveler
The first known use of adversary was in the 14th century


Dictionary Entries Near adversary

Cite this Entry

“Adversary.” Dictionary, Merriam-Webster, Accessed 31 May. 2023.

Kids Definition


1 of 2 noun
ad·​ver·​sary ˈad-və(r)-ˌser-ē How to pronounce adversary (audio)
plural adversaries
: someone or something that struggles with, opposes, or resists : enemy, opponent


2 of 2 adjective
: involving two persons or two sides who oppose each other
our adversary system of justice

Legal Definition


1 of 2 noun
ad·​ver·​sary ˈad-vər-ˌser-ē How to pronounce adversary (audio)
: one that contends with or opposes another
especially : any of the opposing parties in a legal action


2 of 2 adjective
: of, relating to, or involving opposing parties or interests
specifically : of, relating to, or involving a system of justice in which opposing parties usually represented by counsel present evidence to an impartial decision-maker (as a jury) by a process of questioning witnesses under the supervision of a judge compare accusatorial, inquisitorial

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