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

Department of Defense in a San Jose federal court.

From The Wall Street Journal • Jun. 25, 2026

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

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

The tensions grew when the Department of Defense tightened security after several spy scandals.

From "The Woman All Spies Fear" by Amy Butler Greenfield