al·​ly | \ ə-ˈlī How to pronounce ally (audio) , ˈa-ˌlī How to pronounce ally (audio) \
allied; allying

Definition of ally

 (Entry 1 of 3)

transitive verb

: to unite or form a connection or relation between : associate He allied himself with a wealthy family by marriage.

intransitive verb

: to form or enter into an alliance two factions allying with each other


al·​ly | \ ˈa-ˌlī How to pronounce ally (audio) , ə-ˈlī How to pronounce ally (audio) \
plural allies

Definition of ally (Entry 2 of 3)

1 : a sovereign or state associated with another by treaty or league America and its allies
2 : one that is associated with another as a helper : a person or group that provides assistance and support in an ongoing effort, activity, or struggle a political ally She has proven to be a valuable ally in the fight for better working conditions. often now used specifically of a person who is not a member of a marginalized or mistreated group but who expresses or gives support to that group The storyline on "Glee" captures something larger that we are seeing with a new generation of allies (allies are people who support LGBT rights but aren't LGBT themselves).— David M. Hall
3 : a plant or animal linked to another by genetic or taxonomic proximity ferns and their allies


adverb suffix

Definition of -ally (Entry 3 of 3)

: -ly entry 2 terrifically in adverbs formed from adjectives in -ic with no alternative form in -ical

Examples of ally in a Sentence

Verb There may be occasions when America can ally with some of those states, as we did during the Gulf War. — Ramesh Ponnuru, National Review, 15 Oct. 2001 Teresa's right to teach, however, would not be vindicated until our time when the late Paul VI named her a doctor of the church. In her own lifetime Teresa had the good sense to ally herself with outstanding supporters such as the observant Franciscan Peter Alcantara and the famous Dominican theologian, Domenico Báñez. — Lawrence S. Cunningham, Commonweal, 28 Jan. 2000 The singers ally themselves with a gifted songwriter, and everyone gets some major-label exposure for what just happens to be a splendid album. — Michael Azerrad, Rolling Stone, 13-27 July 1995 Generally, however, psychoanalysts do ally themselves with two positions, the first of which is that dreams are meaningful. — Wynn Schwartz, Dreamtime and Dreamwork, 1990 She's allied herself with the moderates on this issue. countries allying themselves with the EU He'll even admit that he's hoping to ally himself to a wealthy family by marriage. They've allied with their former enemies. Noun When the Soviets pulled out in early 1989, the ensuing power vacuum turned former allies into enemies. The Muslim fighters known as mujahideen, who were unified in their struggle against the Soviets, disbanded and fought one another for control of Kabul in a devastating civil war. — Jiffer Bourguignon, Saveur, March 2008 Our allies would need us more than we would need them, so we could count on them to rally to our side in a crunch. — Samantha Power, New York Times Book Review, 29 July 2007 These groups have learned from experience that the media are their most valuable ally. Publicity increases tips that fuel an investigation, and many communities have launched special-alert systems in the past few years to get news of an abduction on the air within minutes. — Andrew Murr, Newsweek, 29 July 2002 fought with the Allies in World War II She's counting on her allies in the state legislature. See More
Recent Examples on the Web: Verb Traditionally, to address this problem, France would ally itself with Britain. Tom Mctague, The Atlantic, 4 Apr. 2022 The government of Ukrainian President Volodymyr Zelensky meanwhile has vowed to fight for Ukrainian sovereignty and defended the country’s right to ally itself with the West. Washington Post, 1 Mar. 2022 Those same warlords would later ally with the U.S.-led coalition to oust the Taliban in 2001. CBS News, 12 Feb. 2022 Then, in the leadup to World War II, King Victor Emmanuel III decided to ally with Benito Mussolini. Bryan Hood, Robb Report, 31 Jan. 2022 Blaming teachers’ unions and Democrats who ally with those unions is also part of this cautionary tale. Rachel M. Cohen, The New Republic, 25 Jan. 2022 Moscow is calling up reserves in Russia and has dispatched troops to ally Belarus, on Ukraine’s northern border. Los Angeles Times, 21 Jan. 2022 The Cold War ended 30 years ago this month, but one unresolved issue – how closely Ukraine, a former Soviet republic, can ally with the West – is now creating some of the deepest U.S.-Russian tensions in years. Robert Burns, ajc, 6 Dec. 2021 But that's precisely why the country needs liberal-minded leftists to ally with liberal centrists in taking a stand against the pious simplicities proffered by illiberal ideologues on both extremes. Damon Linker, The Week, 25 June 2021 Recent Examples on the Web: Noun Jordan, a close ally of former President Donald Trump, had previously declined to talk with the committee. Jessie Balmert, The Enquirer, 12 May 2022 And read Shawn Tully’s story on how Elon Musk converted Saudi Prince Alwaleed bin Talal from opponent to ally of his Twitter deal. David Meyer, Fortune, 11 May 2022 Kirill, an ally of Russian President Vladimir Putin who has justified Russia’s military operations abroad, is one of nearly 60 people facing travel bans and asset freezes under the EU plans. Robert Hart, Forbes, 6 May 2022 The government has called Abramovich a close ally of Russia’s president, Vladimir V. Putin. Tariq Panja, New York Times, 6 May 2022 Belarus, an ally of Russia, said the exercises posed no threat to its neighbors or the rest of Europe. Los Angeles Times, 4 May 2022 Belarusian President Alexander Lukashenko, a close ally to Russian President Vladimir Putin, allowed Russian troops to assemble and conduct military drills in the Eastern European country in the run-up to Moscow’s invasion of Ukraine on Feb. 24. Washington Post, 4 May 2022 The close ally of Orban and staunch supporter of former U.S. President Donald Trump has for years been accused in his country of eroding its traditional democratic standards. Ali Zerdin, ajc, 25 Apr. 2022 Jansa is an effusive admirer of former U.S. President Donald Trump and a key ally of Hungarian Prime Minister Viktor Orban. Peter Weber, The Week, 24 Apr. 2022 See More

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

First Known Use of ally


14th century, in the meaning defined at transitive sense


1598, in the meaning defined at sense 1

History and Etymology for ally

Verb and Noun

Middle English allien, from Anglo-French alier, from Latin alligare to bind to, from ad- + ligare to bind — more at ligature

Adverb suffix

-al entry 1 + -ly

Learn More About ally

Time Traveler for ally

Time Traveler

The first known use of ally was in the 14th century

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Last Updated

10 Apr 2022

Cite this Entry

“Ally.” Dictionary, Merriam-Webster, Accessed 25 May. 2022.

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More Definitions for ally


al·​ly | \ ˈa-ˌlī How to pronounce ally (audio) , ə-ˈlī \
plural allies

Kids Definition of ally

 (Entry 1 of 2)

: a person, group, or nation associated or united with another in a common purpose


al·​ly | \ ə-ˈlī How to pronounce ally (audio) , ˈa-ˌlī \
allied; allying

Kids Definition of ally (Entry 2 of 2)

: to form a connection between : join in an alliance

More from Merriam-Webster on ally

Nglish: Translation of ally for Spanish Speakers

Britannica English: Translation of ally for Arabic Speakers


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