uni·​lat·​er·​al | \ ˌyü-ni-ˈla-tə-rəl How to pronounce unilateral (audio) , -ˈla-trəl\

Definition of unilateral

1a : done or undertaken by one person or party
b : of, relating to, or affecting one side of a subject : one-sided
c : constituting or relating to a contract or engagement by which an express obligation to do or forbear is imposed on only one party
2a : having parts arranged on one side a unilateral raceme
b : occurring on, performed on, or affecting one side of the body or one of its parts unilateral exophthalmos
3 : unilineal
4 : having only one side

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Other Words from unilateral

unilaterally adverb

Did You Know?

The world is a smaller place than it used to be, and we get uncomfortable when a single nation adopts a policy of unilateralism—that is, acting independently with little regard for what the rest of the world thinks. A unilateral invasion of another country, for instance, usually looks like a grab for power and resources. But occasionally the world welcomes a unilateral action, as when the U.S. announced unilateral nuclear-arms reductions in the early 1990s. Previously, such reductions had only happened as part of bilateral ("two-sided") agreements with the old Soviet Union. Multilateral agreements, on issues such as climate change, often involve most of the world's nations.

Examples of unilateral in a Sentence

Our country is prepared to take unilateral action.

Recent Examples on the Web

The tensions, set off by India’s swift and unilateral decision last month to wipe out Kashmir’s autonomy, are no longer as simple as protesters pelting security officers with rocks and the officers firing shotguns back. Suhasini Raj, New York Times, "Abused by Soldiers and Militants, Kashmiris Face Dangers in Daily Life," 15 Sep. 2019 So far, North Korea has stuck by its unilateral suspension of nuclear and long-range missile tests, which came during a diplomatic outreach to Washington last year. Fox News, "North Korea again fires projectiles into Sea of Japan, officials say," 10 Aug. 2019 The 2015 deal with world powers has steadily unraveled following President Donald Trump’s unilateral withdrawal of the U.S. from the accord last year. Washington Post, "Iran defends plan for further steps away from nuclear deal," 6 Sep. 2019 Under the deal, which has steadily unraveled after President Trump’s unilateral withdrawal of the United States from the accord last year, experts thought Iran would need about a year to reach that point. Jon Gambrell, BostonGlobe.com, "Iran poised for faster centrifuges as nuclear deal collapses," 5 Sep. 2019 These type of exercises, called unilateral moves, challenge your balance and require your core to work a bit harder to keep you stable. Amy Marturana, SELF, "7 Dumbbell Exercises That Work Your Core," 30 May 2019 The comments drew immediate international attention because Trump had been so defiant with his unilateral decision to engage in a trade war with China. Anchorage Daily News, "Trump says he wishes he’d raised tariffs even higher on China as trade war escalates," 25 Aug. 2019 The information blockade was an integral part of India’s unilateral decision last week to wipe out the autonomy of Jammu and Kashmir, an area of 12.5 million people that is claimed by both India and Pakistan and has long been a source of tension. New York Times, "India Shut Down Kashmir’s Internet Access. Now, ‘We Cannot Do Anything.’," 14 Aug. 2019 But many Europeans have said a unilateral U.S. decision potentially weakens European security and plays into Russian positioning that Washington is abandoning arms-control, not Moscow. Jessica Donati, WSJ, "NATO Meeting to Be Dominated by Russia-Ukraine Clash," 3 Dec. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unilateral.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of unilateral

1802, in the meaning defined at sense 1a

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Statistics for unilateral

Last Updated

16 Oct 2019

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The first known use of unilateral was in 1802

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English Language Learners Definition of unilateral

: involving only one group or country


uni·​lat·​er·​al | \ ˌyü-ni-ˈlat-ə-rəl, -ˈla-trəl How to pronounce unilateral (audio) \

Medical Definition of unilateral

: occurring on, performed on, or affecting one side of the body or one of its parts unilateral exophthalmos

Other Words from unilateral

unilaterally \ -​ē How to pronounce unilaterally (audio) \ adverb


uni·​lat·​er·​al | \ ˌyü-nə-ˈla-tə-rəl How to pronounce unilateral (audio) \

Legal Definition of unilateral

1 : done or undertaken by one party a unilateral mistake as to the terms
2 : of, relating to, or affecting one side of a subject
3 : containing a promise to perform made by only one party especially because the other has already performed (as by paying an amount) an option contract is unilateral

Other Words from unilateral

unilaterally adverb

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More from Merriam-Webster on unilateral

Spanish Central: Translation of unilateral

Nglish: Translation of unilateral for Spanish Speakers

Britannica English: Translation of unilateral for Arabic Speakers

Comments on unilateral

What made you want to look up unilateral? Please tell us where you read or heard it (including the quote, if possible).


to fake an opponent out of position

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