1. A noncommissioned officer serving as chief administrative officer of a headquarters unit of the Army
   "The command sergeant major ensured that all personnel adhered to military regulations";
   - command sergeant major
    
2. Large blue-grey black-striped damselfish; nearly worldwide
   "The sergeant major is a common sight on coral reefs";
   - Abudefduf saxatilis

Derived forms: sergeants major, sergeant majors

Type of: damselfish, demoiselle [archaic], sarge [informal], sergeant

Part of: Abudefduf, genus Abudefduf

Encyclopedia: Sergeant major