Chief of Staff

American  

noun

1. the senior officer of the U.S. Army or Air Force, a member of the Joint Chiefs of Staff, responsible to the secretary of a service branch.

2. (lowercase) the senior or principal staff officer in a brigade or division or higher unit in the U.S. Army or Marine Corps, in a numbered unit in the U.S. Air Force, or in a unit in the U.S. Navy commanded by a rear admiral or one of higher rank.

3. (lowercase) the senior officer in command of a general staff, especially that of the military forces of a nation.

4. (lowercase) the head of any staff.

   the chief of staff for the First Lady.

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Chief of Staff British  

noun

1. the senior staff officer under the commander of a major military formation or organization

2. the senior officer of each service of the armed forces

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Etymology

Origin of Chief of Staff

First recorded in 1880–85

Example Sentences

A video posted late on Wednesday by Deputy White House Chief of Staff Dan Scavino recorded Trump saying he would nominate Blanche "tomorrow", adding that he thought the Senate confirmation process would go "very quickly".

From BBC • Jun. 4, 2026

But Army Secretary Dan Driscoll and acting Army Chief of Staff Christopher LaNeve acknowledged during their testimony on Friday that they were only told the deployment had been canceled a couple of days ago.

From The Wall Street Journal • May 15, 2026

The central figure making this case, according to several accounts, is Gen. Dan Caine, the Trump-appointed chairman of the Joint Chief of Staff.

From Slate • Feb. 28, 2026

Twelve candidates, including Price’s Deputy Chief of Staff Jose Ugarte, have entered the race to represent District 9 after he terms out.

From Los Angeles Times • Feb. 8, 2026

Air Force Chief of Staff Curtis LeMay was once asked how he would deal with Fidel Castro’s Cuba.

From "Fallout: Spies, Superbombs, and the Ultimate Cold War Showdown" by Steve Sheinkin