Department of Defense

American  

noun

1. the department of the U.S. federal government charged with ensuring that the military capacity of the U.S. is adequate to safeguard the national security. DOD

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Department of Defense Cultural  

1. A department of the federal executive branch entrusted with formulating military policies and maintaining American military forces. Its top official is the civilian secretary of defense. It is headquartered in the Pentagon.

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Example Sentences

Others were concerned too, including the Federal Bureau of Investigation and the Department of Defense.

From The Wall Street Journal • Apr. 3, 2026

On Wednesday, the company said it had signed an agreement with the US Department of Defense to "quadruple" production of the munition.

From BBC • Mar. 27, 2026

Department of Defense plans to make the company’s Maven digital battle-management system an official program of record.

From Barron's • Mar. 24, 2026

That led to the Department of Defense designating Anthropic as a supply chain risk and barring the use of its tools at the Pentagon, following a six-month phase-out.

From Salon • Mar. 23, 2026

As an analyst for the Rand Corporation, a think tank focused on military and international issues, he had been granted permission to conduct research at the Pentagon, home of the United States Department of Defense.

From "Most Dangerous: Daniel Ellsberg and the Secret History of the Vietnam War" by Steve Sheinkin