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 Russia has recently sought to ally itself with Ethiopia — once a steadfast partner of the West. Adam Taylor, Washington Post, 28 July 2022 Netanyahu’s refusal to resign despite standing trial on corruption charges had alienated many of his natural allies on the right, leading some of them to ally with their ideological opponents to remove him from office. Isabel Kershner,, 20 June 2022 Then, in the ISIS years, the US chose to ally with the Iraqi/Syrian Kurds to extirpate ISIS. Melik Kaylan, Forbes, 6 July 2022 The government, led by Viktor Yanukovych, had arbitrarily reversed the Ukrainian parliament’s decision to ally with the European Union, deepening ties with Russia instead. Ed Caesar, The New Yorker, 20 June 2022 Four years later, Prohibition’s end turns Tommy toward the opium trade, forcing him to ally with his worst enemies. Jacob Siegal, BGR, 5 June 2022 His reluctance to impose sanctions beyond what European partners were ready to do — and his deliberate deference — has reflected a strong commitment to ally management. Eli Stokolsstaff Writer, Los Angeles Times, 23 Mar. 2022 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 Recent Examples on the Web: Noun Gaetz is an ally of former president Donald Trump and was first elected to Congress in 2016, representing a district in the Florida Panhandle, an area that has voted heavily Republican in recent decades., 27 July 2022 Gaetz is an ally of former president Donald Trump and was first elected to Congress in 2016, representing a district in the Florida Panhandle, an area that has voted heavily Republican in recent decades. Andrew Jeong, Washington Post, 27 July 2022 However, Cruz became an ally of Trump's following his election victory. Sarah Rumpf, Fox News, 23 July 2022 Barkley has spoken openly before about how being an ally to the LGBTQ+ community and other marginalized groups is an extension of his lived experience as a Black man. Philip Ellis, Men's Health, 20 July 2022 Scott’s father, Michael Scott, was a close ally to Mayor Richard M. Daley who rose to become president of the Chicago Board of Education. Chicago Tribune, 15 July 2022 Ming-Na Wen, whose character is an ally of a certain tiny green Jedi-in-training. Scottie Andrew, CNN, 14 July 2022 How can your colleagues be an ally and create space for others? Karen Pavlin, Forbes, 11 July 2022 But the move has been opposed by Hungarian Prime Minister Viktor Orbán, who has been an ally of Russian President Vladimir Putin. Shannon Pettypiece, NBC News, 29 June 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

8 Aug 2022

Cite this Entry

“Ally.” Dictionary, Merriam-Webster, Accessed 9 Aug. 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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