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

Meanwhile, despite Anthropic's ongoing lawsuit against the US Department of Defense over its refusal to accept government use of its AI tools, US government agencies have been testing Mythos too.

From BBC • Jun. 9, 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

They gathered at the Lincoln Memorial to listen to speeches, then many of them marched on the Pentagon, headquarters of the United States Department of Defense.

From "Boots on the Ground: America's War in Vietnam" by Elizabeth Partridge