- sergeant major - a noncommissioned officer serving as chief administrative officer of a headquarters unit of the army
--1 is a kind of police sergeant, sergeant
- sergeant major, Abudefduf saxatilis - large blue-gray black-striped damselfish; nearly worldwide
--2 is a kind of damselfish, demoiselle
--2 is a member of Abudefduf, genus Abudefduf - sergeant major, Abudefduf saxatilis - large blue-gray black-striped damselfish; nearly worldwide