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

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

The problem: Naval escorts for tankers through such a narrow waterway in a war zone would be nearly impossible, say allied officials and military experts.

From The Wall Street Journal • Apr. 4, 2026

Pararescue teams deployed extensively throughout the wars in Iraq and Afghanistan, conducting thousands of missions to rescue US and allied troops that were wounded or required extraction.

From BBC • Apr. 3, 2026

For in the rich and moist and wanted areas of the world, life pyramids against itself and in its confusion has finally allied itself with the enemy non-life.

From "Travels with Charley in Search of America" by John Steinbeck