allied

American  

[uh-lahyd, al-ahyd] / əˈlaɪd, ˈæl aɪd /

adjective

1. joined by treaty, agreement, or common cause.

   allied nations.

2. related; kindred.

   allied species.

   Synonyms:

   akin

3. Allied, of or relating to the Allies.

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allied ¹ British  

/ ˈælaɪd, əˈlaɪd /

adjective

1. joined, as by treaty, agreement, or marriage; united

2. of the same type or class; related

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Allied ² British  

/ ˈælaɪd /

adjective

1. of or relating to the Allies

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Other Word Forms

• nonallied adjective
• preallied adjective
• unallied adjective
• well-allied adjective

Etymology

Origin of allied

A Middle English word dating back to 1250–1300; see origin at ally, -ed ²

Explanation

Allied means united or joined together. If two countries are allied, they are on the same side and have common interests. When two people are allied, they are friendly — or at least cooperative. To be allied means to have an agreement to work together, so when politicians are allied on a bill, they've pledged to join forces and unite for a common cause. In a war, allied countries are fighting on the same side. Allied comes from ally, which first meant "join in marriage," from the Latin root alligare, "bind to."

Example Sentences

Startups and allied defense industries are filling it, and investors who track those contracts will find the positions before the consensus does.

From MarketWatch • Apr. 13, 2026

Planet initially said its original 14-day delay policy was "to ensure our imagery is not tactically leveraged by adversarial actors to target allied and Nato-partner personnel and civilians".

From BBC • Apr. 11, 2026

An executive order from Trump in December 2025, entitled “Ensuring American Space Superiority,” called for “creating a responsive and adaptive national security space architecture” through allied cooperation and private sector investments.

From Salon • Apr. 9, 2026

It may set an example for other strongmen too: Max is now available for download in dozens of countries allied with Moscow.

From The Wall Street Journal • Apr. 1, 2026

Charles had written about this very idea in his notebooks before the wedding—“Belief allied to instinct.”

From "Charles and Emma: The Darwins' Leap of Faith" by Deborah Heiligman