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

It even engaged in a public dispute with the US Department of Defense over concerns that its AI tools would be used in mass surveillance of Americans and autonomous warfare.

From BBC • Jun. 4, 2026

Department of Defense announced a new multi-billion dollar contract with the computer maker.

From Barron's • May 28, 2026

It puts you in contact with the continuity of government systems—I would imagine the intelligence community and the Department of Defense.

From Slate • May 21, 2026

In late April, President Donald Trump requested a record-breaking $1.5 trillion defense budget, which, if approved, would mark the largest ever increase in Department of Defense funding.

From Salon • May 8, 2026

Your sister, Celie Dear Nettie, The only piece of mail Mr. ever put directly in my hand is a telegram that come from the United States Department of Defense.

From "The Color Purple" by Alice Walker