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

Northern Command, which oversees the Joint Task Force, said questions should be directed to the Department of Homeland Security because they directed the Department of Defense to install the wire.

From Los Angeles Times • Jun. 3, 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

China is also increasing its use of AI-enabled military systems, according to a US Department of Defense assessment published last year.

From BBC • May 6, 2026

Initially, the US Department of Defense oversaw space matters, but President Eisenhower saw the need for a civilian space agency.

From "Women in Space" by Karen Bush Gibson