- the chief administrative noncommissioned officer in a military headquarters: an occupational title and not a rank
- ☆ U.S. Army, U.S. Marine Corps the highest ranking noncommissioned officer
- a small damselfish (Abudefduf saxatilis) with several dark, wide, vertical stripes on its bright-yellowish upper body
See sergeant major in American Heritage Dictionary 4
noun pl. sergeants major sergeants major
or sergeant majors
a. Abbr. SGM or SgtMaj Used as a title for a noncommissioned officer serving as chief administrative assistant of a headquarters unit of the U.S. Army or Marine Corps.
b. One who holds this title.
- Chiefly British A noncommissioned or warrant officer of the highest rank in a company or unit of battalion size.
- A small damselfish (Abudefduf saxatilis) of warm seas, having a flattened body with dark vertical stripes. Also called cow pilot.