ally

noun

plural allies
Synonyms of allynext
1
a
: a sovereign or state associated with another by treaty or league
America and its allies
b
the Allies : the nations that fought together against Germany in World War I or World War II
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
The teacher's union has found an unlikely ally in the company.
She's counting on her allies in the state legislature.
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

Examples of ally in a Sentence

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.
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.
Shah’s closest ally (and the person most willing to call Shah on his lies to himself and others) is his cousin Zulfi, a gigantic character who Khan energizes with fast-talking charm, sarcastic asides, and an assessing glare that can cut through anyone’s defenses. Joe Reid, Vulture, 29 May 2026 Massive drills of Russia’s nuclear forces earlier this month and a series of belligerent statements from Moscow warning Kyiv’s European allies about possible retaliation for what the Kremlin cast as their involvement in Ukrainian drone attacks have underlined Putin’s intention to up the ante. Los Angeles Times, 29 May 2026 There were the longtime Democratic allies who became fair-weather friends. Susan Page, USA Today, 29 May 2026 Phillips said the couple and their allies spent $10 million boosting Obama in the 2008 presidential primary. Ben Paviour, Sacbee.com, 29 May 2026 See All Example Sentences for ally

Word History

Etymology
First Known Use

15th century, in the meaning defined at sense 2

Time Traveler
The first known use of ally was in the 15th century

Browse Nearby Words

Cite this Entry

“Ally.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ally. Accessed 9 Jun. 2026.

Kids Definition

ally

1 of 3 verb
allied; allying
: to form a connection or relation between : unite
especially : to join in an alliance

ally

2 of 3 noun
plural allies
1
: a plant or animal linked to another by genetic or evolutionary relationship
ferns and their allies
2
a
: one associated or united with another for some common purpose
b
plural capitalized : the Allied nations in World War I or World War II

-ally

3 of 3 adverb suffix
-al·​ly
(ə-)lē
Etymology

Middle English allien "unite," from early French alier (same meaning), derived from Latin al-, ad- "to" and ligare "to bind" — related to ligament

from 1-al + -ly

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