Noun
(UK) NATO rank OR-8 in all British armed services.
(UK, Army) A warrant officer in the British Army ranking above staff sergeant and below warrant officer class 1; company sergeant major
(UK, Marines) A warrant officer in the Royal Marines ranking above colour sergeant and below warrant officer class 1.
(UK, Navy) A warrant officer in the Royal Navy ranking above chief petty officer and below warrant officer class 1.
(Australia, Army) A warrant officer in the Australian Army, ranking above sergeant and below warrant officer class 1.
Source: en.wiktionary.org