Noun
company sergeant major (plural company sergeants major or company sergeant majors)
(UK) An appointment in the army, the senior warrant officer in a company, usually held by a warrant officer class 2.
He was also known for his roles as Sergeant Grimshaw, the title character of the first Carry On film, Carry On Sergeant in 1958, and Company Sergeant Major Percy Bullimore in the sitcom The Army Game from 1957 until 1958, and again in 1960. Source: Internet