sergeant major

American  

noun

1. U.S. Army, Air Force, and Marine Corps. a noncommissioned officer serving as chief administrative assistant in a unit headquarters.

2. U.S. Marine Corps. a noncommissioned officer ranking above a first sergeant.

3. a small damselfish, Abudefduf saxatilis, inhabiting warm Atlantic waters, having vertical black stripes on each side.

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sergeant major British  

noun

1. a noncommissioned officer of the highest rank or having specific administrative tasks in branches of the armed forces of various countries

2. a large damselfish, Abudefduf saxatilis, having a bluish-grey body marked with black stripes

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Etymology

Origin of sergeant major

First recorded in 1565–75

Example Sentences

See Examples For:

sergeant major

For example, there is George Williams, a decorated sergeant major with the Kings African Rifles.

From BBC ● Nov. 7, 2025

Sen. Amy Klobuchar of Minnesota also intervened on his behalf along with the service’s top noncommissioned officer, the sergeant major of the Army.

From Seattle Times ● May 16, 2024

“What matters most is making the very best Marines,” said Troy E. Black, sergeant major of the Marine Corps.

From Washington Times ● May 3, 2023

Soon after, he was promoted ahead of 500 other enlisted men to sergeant major, the highest Army rank for a noncommissioned officer.

From Washington Post ● Jan. 19, 2023

He thinks of the colonel with his perfect jawline and flared pants; he thinks of the sallow sergeant major eyeing him over the top of the newspaper.

From "All the Light We Cannot See" by Anthony Doerr