Army and Royal Marines are as follows: Marine (Mne) in the Royal Marines; Air Trooper (ATpr) in the Army Air Corps; Gunner (Gnr) in the Royal Artillery and Royal Horse Artillery; Highlander (Hdr) in The Highlanders (Seaforth, Gordons and Camerons); Ranger (Rgr) in the Royal Irish Regiment; Sapper (Spr) in the Royal Engineers; Trooper (Tpr) in the Household Cavalry, Royal Armoured Corps regiments, Honourable Artillery Company and Special Air Service; Craftsman (Cfn) in the Royal Electrical and Mechanical Engineers; Guardsman (Gdn) in Foot Guards regiments; Kingsman (Kgn) in the Duke of Lancaster's Regiment; Rifleman (Rfn) in The Rifles; Signaller (Sig) in the Royal Corps of Signals; Fusilier (Fus) in the Royal Regiment of Fusiliers and Royal Highland Fusiliers; Musician (Mus) in the Royal Corps of Army Music; Where appropriate: Drummer (Dmr), Trumpeter (Tptr), Bugler, or Piper (Ppr). In the US Army, first sergeant is considered senior to and promoted laterally from master sergeant when assigned to a first sergeant billet, typically the senior NCO in a company (troop, battery)-sized unit. Upon reassignment a 1SG reverts to his previous rank of MSG. In the USMC the OR-8 ranks are equivalent but on separate career tracks as are the OR-9 ranks, i.e. a gunnery sergeant (OR-7) is promoted to either first sergeant or master sergeant depending on his indicated preference for a command/senior enlisted advisor billet or a technical specialty. A first sergeant is promoted to sergeant major and a master sergeant to master gunnery sergeant. The alternatives to the rank of seaman in the US Navy are as follows: Fireman (FN) in engineering; Airman (AN) in aviation; Hospitalman (HN) for medical corpsmen; Constructionman (CN) in Construction Battalions (Seabees). The former rate of Dentalman (DN) was merged into Hospitalman in 2005. Also Fireman Apprentice (FA), Airman Apprentice (AA), Hospitalman Apprentice (HA), Constructionman Apprentice (CA). Also Fireman Recruit (FR), Airman Recruit (AR), Hospitalman Recruit (HR), Constructionman Recruit (CR). The senior most NCO in each Service has a unique title, and in the US Services a unique set of rank/rating insignia. See also List of comparative military ranks Ranks and insignia of NATO British Army officer rank insignia British Army other ranks rank insignia U.S. Army officer rank insignia U.S. Army enlisted rank insignia Military rank References External links NATO codes for grades of military personnel in STANAG 2116 Military ranks of the United Kingdom Military ranks of the United States Ranks ja:軍隊における階級呼称一覧 zh:軍階