Ship prefix - wikipedia Ship prefix Wikimedia list article This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. ( January 2009 ) A ship prefix is a combination of letters, usually abbreviations, used in front of the name of a civilian or naval ship. Prefixes for civilian vessels may either identify the type of propulsion, such as `` PS '' for paddle steamer, or purpose, such as `` RV '' for research vessel. Civilian prefixes are often used inconsistently, and frequently not at all. Sometimes a slash is used to separate the letters, as in `` M / S ''. Naval prefixes came into use as abbreviations for longer titles, such as `` His / Her Majesty 's Ship '' in the British Royal Navy, abbreviated `` H.M.S. '' and then `` HMS ''. Earlier uses often included the type of vessel, as for instance `` U.S.F. '' ( `` United States Frigate '' ) for frigates of the United States Navy, that were eliminated by President Theodore Roosevelt 's Executive order of 1907 making `` United States Ship '' ( USS ) the standard for the Navy 's commissioned ships while in commission. In the United States Navy that prefix officially only applies while the ship is in active commission, with only the name used before or after a period of commission and for all vessels `` in service '' rather than commissioned status. Today the common practice is to use a single prefix for all warships of a nation 's navy, and other prefixes for auxiliaries and ships of allied services, such as coast guards. The use of ship prefixes is not universal ; in particular neither the German Kriegsmarine nor the Imperial Japanese Navy used ship prefixes, though the suffix Maru meaning `` circle '' is common for most Japanese civilian vessels. Some English - language writers use prefixes like `` DKM '' ( for `` Deutsche Kriegsmarine '' ) and `` HIJMS '' ( for `` His Imperial Japanese Majesty 's Ship '' ) or `` IJN '' ( for `` Imperial Japanese Navy '', a translation of 大 日本 帝国 海軍 dai - nippon teikoku kaigun ) for consistency with `` HMS '' and `` USS ''. Other writers follow the practice of the navy and omit any prefix. From the 20th century onwards, most navies identify ships by hull numbers ( pennant numbers ) -- identification codes typically painted on the side of the ship. Each navy has its own system : the United States Navy uses hull classification symbols, and the Royal Navy and other navies of Europe and the Commonwealth use pennant numbers. These tables list both current and historical prefixes known to have been used. Contents 1 Generic ( merchant navy ) prefixes 2 National or military prefixes 2.1 Prefix conventions 3 In science fiction 4 References 4.1 Notes 4.2 Sources 5 External links Generic ( Merchant Navy ) prefixes AHTS Balder Viking FPSO Noble Seillean These prefixes are generally used for merchant vessels of any nationality. Prefix Meaning AE Ammunition ship AFS Combat stores ship AHT Anchor Handling Tug AHTS Anchor Handling Tug Supply vessel AO United States Navy oiler AOG Gasoline tanker AOR Auxiliary, Replenishment Oiler AOT Transport Oiler ATB Articulated Tug Barge CRV Coastal Research Vessel C / F Car Ferry CS Container Ship, Cable Ship DB Derrick Barge DEPV Diesel Electric Paddle Vessel DLB Derrick Lay Barge DCV Deepwater Construction Vessel DSV Diving Support Vessel / Deep Submergence Vehicle DV Dead vessel ERRV Emergency Response Rescue Vessel FPSO Floating Production, Storage and Offloading Vessel FPV Free Piston Vessel FPV Fishery Protection Vessel FT Factory Stern Trawler FV Fishing Vessel GTS Gas Turbine Ship HLV Heavy lift vessel HMT Hired Military Transport ( not currently in use ) HSC High Speed Craft HSF High Speed Ferry HTV Heavy Transport Vessel IRV International Research Vessel ITB Integrated Tug barge LB Liftboat LNG / C Liquefied natural gas carrier LPG / C Liquefied petroleum gas carrier MF Motor Ferry MFV Motor Fishing Vessel ( mainly UK Royal Naval Reserve ) MS ( M / S ) Motor Ship ( interchangeable with MV ) MSV Multipurpose support / supply vessel MSY Motor Sailing Yacht MT Motor Tanker MTS Marine Towage and Salvage / Tugboat MV ( M / V ) Motor Vessel ( interchangeable with MS ) MY Motor Yacht NB Narrowboat NRV NATO Research Vessel NS Nuclear Ship OSV Offshore supply vessel PS Paddle Steamer PSV Platform Supply Vessel QSMV Quadruple Screw Motor Vessel QTEV Quadruple Turbo Electric Vessel RMS Royal Mail Ship or Royal Mail Steamer RNLB Royal National Lifeboat RRS Royal Research Ship RV / RSV Research Vessel SB Sailing Barge SS ( S / S ) Single - screw Steamship ( also usage as generic term for any steamship ) SSCV Semi-Submersible Crane Vessel SSS Sea Scout Ship SSV Sailing School Vessel, Submarine and Special Warfare Support Vessel ST Steam Tug or Steam Trawler STS Sail Training Ship STV Sail Training Vessel or Steam Turbine Vessel SV ( S / V ) Sailing Vessel SY Sailing Yacht or Steam Yacht TB Tug boat TEV Turbine Electric Vessel TIV Turbine Installation Vessel TrSS Triple - Screw Steamship or steamer TS Training Ship or Turbine Steamship or Turbine steam ship Tr. SMV Triple - Screw Motor Vessel TSMV Twin - Screw Motor Vessel TSS Twin - Screw Steamship or steamer TST Twin - Screw Tug TV Training vessel VSS Virgin SpaceShip, ( space - going experimental air planes by Virgin Galactic ) YD Yard Derrick YW Water Barge, self - propelled YOS Concrete vessel National or military prefixes Country Service Prefix Meaning Argentina Argentine Navy ARA Navy of the Argentine Republic ( Spanish : Armada de la República Argentina ) Argentine Coast Guard GC Argentine Coast Guard Ship ( Spanish : Guardacostas ) Australia Royal Australian Navy HMAS His / Her Majesty 's Australian Ship / Submarine / Station NUSHIP New Ship / Submarine ( Yet to be commissioned ) ADV Australian Defence Vessel ( non-commissioned naval - operated ships ) MSA Minesweeper Auxiliary Australian Customs and Border Protection Service ACV Australian Customs Vessel Australian Border Force ABFC Australian Border Force Cutter Australia ( pre-Federation ) Colonial navies of Australia HMCS His / Her Majesty 's Colonial Ship HMQS His / Her Majesty 's Queensland Ship ( Queensland Maritime Defence Force ) HMVS His / Her Majesty 's Victorian Ship ( Victorian Naval Forces ) Austria - Hungary Austro - Hungarian Navy SMS Seiner Majestät Schiff ( English : His Majesty 's Ship ) Bahamas Royal Bahamas Defence Force HMBS His / Her Majesty 's Bahamian Ship Bangladesh Bangladesh Coast Guard CGS Coast Guard Ship Bangladesh Navy BNS Bangladesh Navy Ship Barbados Barbados Defence Force HMBS His / Her Majesty 's Barbadian Ship Belgium Belgian Navy BNS Belgium Naval Ship ( NATO prefix ) Brunei Royal Brunei Navy KDB Kapal Di - Raja Brunei -- Royal Brunei Ship Burma Myanmar Navy UMS Myanmar Sit Yay Yin -- Union of Myanmar Ship Bulgaria Bulgarian Navy -- none -- Canada Royal Canadian Navy, formerly Canadian Forces Maritime Command HMCS / NCSM His / Her Majesty 's Canadian Ship / Navire canadien de Sa Majesté ( French ) CFAV / NAFC Canadian Forces Auxiliary Vessel / Navire auxiliaire des Forces canadiennes ( French ) Canadian Coast Guard CCGS / NGCC Canadian Coast Guard Ship / Navire de Garde côtière canadienne ( French ) CCGC / CGCC Canadian Coast Guard Cutter / Cotre de Garde côtière canadienne ( French ) ( no longer used ) Department of Fisheries and Oceans, Department of Transport, and predecessor departments CGS Canadian Government Ship ( no longer used ) CSS Canadian Survey Ship ( no longer used ) DGS Dominion Government Ship ( no longer used ) Royal Canadian Sea Cadets SCTS / NECM Sea Cadet Training Ship / Navire école des cadets de la Marine ( French ) China People 's Liberation Army Navy -- No official prefix ; some authors use `` CNS '' ( Chinese Navy Ship ) or `` PLANS '' ( People 's Liberation Army Navy Ship ) Colombia Armada Nacional ARC Armada de la República de Colombia Confederate States Confederate States Navy CSS Confederate States Ship Cook Islands Cook Islands Police CIPPB Cook Islands Police Patrol Boat Denmark Royal Danish Navy HDMS ( Danish : KDM ) His / Her Danish Majesty 's Ship ( Danish : Kongelige Danske Marine ) Ecuador Armada Ecuatoriana BAE Buque de la Armada de Ecuador Estonia Estonian Navy ENS ( Estonian : EML ) Estonian Naval Ship ( NATO designation ) Estonian Coast Guard ECGS Estonian Coast Guard Ship ( NATO designation ) Fiji Republic of Fiji Navy RFNS Republic of Fiji Naval Ship Finland Finnish Navy FNS Finnish Navy Ship. Prefixes are not used in Finnish - language communications. France French Navy OF Okręt Francuski ( Polish French Ship ) ; used in 1940 -- 41 for French destroyer Ouragan FS French Ship ( NATO designation ) ; France does not use prefixes internally German Empire Kaiserliche Marine SM U # # Seiner Majestät Unterseeboot ( English : His Majesty 's Submarine ) SMS Seiner Majestät Schiff ( English : His Majesty 's Ship ) Nazi Germany Kriegsmarine -- ( no prefix ; some authors use `` DKM '' for `` Deutsche Kriegsmarine '' and `` KMS '' for `` Kriegsmarine Schiffe '' ) West Germany Bundesmarine FGS Federal German Ship ( NATO designation ; West Germany did not use prefixes internally ) Germany ( reunited ) German Navy FGS Federal German Ship ( NATO designation, German ships do not use prefixes internally ) Kingdom of Greece Royal Hellenic Navy ΒΠ ( VP ) Βασιλικόν Πλοίον ( Vassilikón Ploíon ), `` Royal Ship '' ; RHS ( Royal Hellenic Ship ) or HHMS ( His Hellenic Majesty 's Ship ) in use by English - language authors and contemporary foreign navies. Greece Hellenic Navy HS Hellenic Ship : NATO designation, used in international communications ; internally the Hellenic Navy uses prefixes indicating ship type. Guyana Guyanese Coast Guard GDFS Guyanese Defence Forces Ship Kingdom of Hawaii Hawaiian Navy HHMS His Hawaiian Majesty 's Ship ; the only one being Kaimiloa Iceland Icelandic Coast Guard ICGV ( Icelandic : VS ) Icelandic Coast Guard Vessel, ( Icelandic : Varðskip ) India Indian Navy ( pre-Republic ) HMIS His / Her Majesty 's Indian Ship India Indian Coast Guard ICGS Indian Coast Guard Ship Indian Navy INS Indian Naval Ship Indonesia Indonesian Navy KRI Kapal Republik Indonesia ( Republic of Indonesia Ship ) Republic of Indonesia KL Kapal Layar ( Sailing Ship ) Republic of Indonesia KM Kapal Motor ( Motor Ship ) Republic of Indonesia KN Kapal Negara ( State Ship ) Iran Imperial Iranian Navy IIS Imperial Iranian Ship ( Persian : ناو شاهنشاهی ایران ) Iran Islamic Republic of Iran Navy IRIS Islamic Republic of Iran ship ( Persian : ناو جمهوری اسلامی ایران ) Ireland Irish Naval Service LÉ Long Éireannach -- Irish ship Israel Israeli Sea Corps INS Israeli Naval Ship ( Internally Hebrew acronym אח `` י ( A. Ch. Y. ) is used standing for אניית חיל הים ( Oniyat Heyl HaYam -- Sea Corps Ship ) Kingdom of Italy ( until 1946 ) Regia Marina RN Regia Nave -- Royal Ship Regia Marina R. Smg. Regio Sommergibile -- Royal Submarine Italy Marina Militare ITS Italian Ship ( NATO designation ) ; Italy no longer uses prefixes Jamaica Jamaica Defence Force HMJS His / Her Majesty 's Jamaican Ship Empire of Japan Imperial Japanese Navy -- ( no prefix ; some authors use `` HIJMS '' for `` His Imperial Japanese Majesty 's Ship '' and `` IJN '' for `` Imperial Japanese Navy '' ) Japan Japan Maritime Self - Defense Force JDS or JS Japanese Defense Ship or Japanese Ship Kenya Kenyan Navy KNS Kenyan Naval Ship Kiribati Kiribati Police Force RKS Republic of Kiribati Ship North Korea Korean People 's Navy -- ( currently unknown ) Kuwait Kuwait Naval Force KNS Kuwait Navy Ship South Korea Republic of Korea Navy ROKS Republic of Korea Ship Latvia Latvian Navy LVNS Latvian Naval Ship ( NATO designation ) Lithuania Lithuanian Navy LKL LNS Lietuvos Karinis Laivas -- Lithuanian Military Ship Lithuanian Ship ( NATO designation ) Malaysia Royal Malaysian Navy KD Kapal Di - Raja -- His Majesty 's Ship, literal : Royal Ship. Malaysian Maritime Enforcement Agency KM Kapal Maritim -- Maritime Ship Marshall Islands Marshall Islands Police RMIS Republic of the Marshall Islands Ship Federated States of Micronesia FSM National Police FSM Federated States of Micronesia Mexico Armada de México ARM Armada de la República Mexicana Myanmar Tatmadaw Yay UMS Myanma Sit Yay Yin -- Union of Myanmar Ship Namibia Namibian Navy NS Namibian Ship Netherlands Royal Netherlands Navy HNLMS ( Dutch : Zr.Ms. / Hr.Ms. ) His / Her Netherlands Majesty 's Ship ( Dutch : Zijner / Harer Majesteits, archaic Dutch language genitive, lit. `` His / Her Majesty 's '' ) New Zealand Royal New Zealand Navy HMNZS His / Her Majesty 's New Zealand Ship Nigeria Nigerian Navy NNS Nigerian Naval Ship Norway Royal Norwegian Navy HNoMS ( Norwegian : KNM ), in use since 1946 His Norwegian Majesty 's Ship ( Norwegian : Kongelige Norske Marine ) Norwegian Coast Guard NoCGV ( Norwegian : KV ) Norwegian Coast Guard Vessel ( Norwegian : Kystvakten ) Oman Royal Navy of Oman SNV Sultanate Naval Vessel Pakistan Pakistan Navy PNS Pakistani Naval Ship Palau Palau Police PSS Palau State Ship Papua New Guinea Papua New Guinea Defence Force HMPNGS His / Her Majesty 's Papua New Guinea Ship Peru Peruvian Navy BAP Peruvian Navy Ship ( Spanish : Buque Armada Peruana ) BIC Scientific Research Ship ( Spanish : Buque de Investigación Científica ) Philippines Philippine Navy BRP Barko ng Republika ng Pilipinas ; in use since 1 July 1980 ( Ship of the Republic of the Philippines ) RPS Republic of the Philippines Ship ( Obsolete ) ; before 1 July 1980 Poland Polish Navy ORP Ship of the Republic of Poland ( Polish : Okręt Rzeczypospolitej Polskiej ) Portugal Marinha Portuguesa NRP Navio da República Portuguesa -- Ship of the Portuguese Republic PNS Portuguese Navy Ship ( NATO designation, not used internally ) UAM Unidade Auxiliar da Marinha -- Navy Auxiliary Unit ( used by the Portuguese Navy non-military ships ) Romania Romanian Navy NMS Nava Majestăţii Sale ( His / Her Majesty 's Ship ) -- used before 1945 by the Royal Romanian Navy SMR Serviciul Maritim Român ( The Romanian Sea Service ) -- used by transport ships ROS Romanian Ship ( NATO designation, not used internally ) Russian Empire Imperial Russian Navy HIRMS ( no prefix ; some authors use `` HIRMS '' for `` His Imperial Russian Majesty 's Ship '' ) Russia Russian Navy -- No official prefix ; some authors use `` RFS '' ( Russian : Корабль Российской Федерации ) Saudi Arabia Saudi Navy HMS His Majesty 's Ship -- the same as the Royal Navy Singapore Republic of Singapore Navy RSS Republic of Singapore Ship Solomon Islands Royal Solomon Islands Police RSIPV Royal Solomon Islands Police Vessel South Africa South African Navy SAS South African Ship ( previously HMSAS -- His / Her Majesty 's South African Ship ) SATS South African Training Ship Soviet Union Soviet Navy -- No official prefix ; some authors use `` USSRS '' ( Russian : Корабль Союза Советских Социалистических Республик ) Spain Armada Española ESPS Spanish Navy Ship ( Spain does not use prefixes internally. ESPN or SPS are no longer used ) Sri Lanka Sri Lankan Navy SLNS Sri Lanka Naval Ship Sweden Swedish Navy HMS ( English : HSwMS ) Hans / Hennes Majestäts Skepp ( His / Her Majesty 's Ship ) -- in English HSwMS ( His / Her Swedish Majesty 's Ship ) is used to avoid confusion with Royal Navy ships Republic of China Republic of China Navy ROCS ( older usage : CNS ) Republic of China Ship ( older usage : Chinese Navy Ship ) Thailand Royal Thai Navy HTMS His Thai Majesty 's Ship Timor - Leste Timor Leste Defense Force NRTL Navio da República de Timor Leste ( Ship of the Timor Leste Republic ) Tonga Tonga Defence Services VOEA Vaka O Ene Afio ( His Majesty 's Vessel ) Turkey Turkish Navy TCG Ship of the Turkish Republic ( Turkish : Türkiye Cumhuriyeti Gemisi. ) Tuvalu Tuvalu Police Force HMTSS His / Her Majesty 's Tuvaluan State Ship Trinidad and Tobago Trinidad and Tobago Defence Force TTS Trinidad and Tobago Ship United Kingdom Ships carrying mail RMS Royal Mail Steamer / Ship Fishery protection vessels FPV Fisheries Protection Vessel Royal Air Force HMAFV His / Her Majesty 's Air Force Vessel ( not currently in use ) Royal Fleet Auxiliary ships RFA Royal Fleet Auxiliary Royal Maritime Auxiliary Service ships RMAS Royal Maritime Auxiliary Ship ( now obsolete ) Royal Naval Auxiliary Service XSV Auxiliary Service Vessel ( now obsolete ) Royal Navy HM Sloop His / Her Majesty 's Sloop ( now obsolete ) HMS His / Her Majesty 's Ship / Submarine HMSm His / Her Majesty 's Submarine ( not currently in use ) HMT Hired Military Transport ( not currently in use ) HMAV His / Her Majesty 's Armed Vessel ( not currently in use ) HMY His / Her Majesty 's Yacht ( not currently in use ) HMMGB His / Her Majesty 's Motor Gun Boat ( not currently in use ) HMM His / Her Majesty 's Monitor ( not currently in use ) HMSML His / Her Majesty 's Small Motor Launch HBMS His / Her Britannic Majesty 's Ship ( archaic ) HM His / Her Majesty 's, then used with the type of ship in military use ( e.g. `` HM Trawler '' ) Hospital Ships HMHS His / Her Majesty 's Hospital Ship Joint Services Sail Training Yachts ( JSASTC ) HMSTC His / Her Majesty 's Sail Training Craft Trinity House THV Trinity House Vessel ( Lighthouse and Buoy Tender ) Northern Lighthouse Board NLV Northern Lighthouse Vessel ( Lighthouse tender ) Commissioners of Irish Lights ILV Irish Lights Vessel ( Lighthouse tender ) British Army HMAV Her Majesty 's Army Vessel RCLV Royal Corps of Logistics Vessel ( not currently in use ) Government research ships RRS Royal Research Ship HM Revenue and Customs / Border Force HMCC, HMC His / Her Majesty 's Customs Cutter shortened to His / Her Majesty 's Cutter after being transferred to Border Force HM Customs and Excise ( replaced by HMRC, above ) HMRC His / Her Majesty 's Revenue Cutter ( not used since 18 April 2005 ). Also His / Her Majesty 's Revenue Cruiser ( as per HMRC Vigilant 1947. Not used since ca1960 ) United States United States Air Force USAF, USAFS United States Air Force ship ( not currently in use ) United States Army ( modern ) USAS United States Army Ship ( modern ) USAV United States Army Vessel ( modern ) United States Army ( historical ) USAT United States Army Transport ( large troop or cargo transports, not currently in use ) USAMP U.S. Army Mine Planter ( not currently in use ) U.S. Army Vessels not otherwise designated : tugs, FS, Q, P etc. ( not currently in use ) USAHS United States Army Hospital Ship ( not currently in use ) United States Navy USF United States Frigate ( obsolete ) USFS United States Flagship ( obsolete ) USS United States Ship -- Commissioned ships only. USNV United States Naval Vessel ( Small utility vessels, not MSC, operated by local commands ) U.S. Navy Military Sealift Command ( MSC ) USNS United States Naval Ship ( USN - owned, civilian crews ) United States Coast Guard USCGC United States Coast Guard Cutter USCGD United States Coast Guard Destroyer ( not currently in use ) National Oceanic and Atmospheric Administration NOAAS National Oceanic and Atmospheric Administration Ship United States Coast and Geodetic Survey USC&GS United States Coast and Geodetic Survey ( obsolete ) ; occasionally a second `` S '' for `` survey ship '' was used United States Commission of Fish and Fisheries USFC United States Fish Commission ( obsolete ) ; commonly used informal name for the Commission ; no `` S '' for `` ship '' was used United States Lighthouse Service USLHT United States Lighthouse Tender ( obsolete ) United States Revenue Cutter Service USRC United States Revenue Cutter ( obsolete ) Uruguay Uruguayan Navy ROU República Oriental del Uruguay Vanuatu Vanuatu Police Force RVS Republic of Vanuatu Ship Venezuela Venezuelan Navy FNV Fuerzas Navales de Venezuela Not in use since 1949 ARV Armada República de Venezuela Not in use 1999 ARBV Armada República Bolivariana de Venezuela Kingdom of Yugoslavia Royal Yugoslav Navy KB Kraljevski brod or Краљевски брод ( English : Royal Ship ), 1918 -- 1941 YUG SCG Jugoslovenska Ratna Mornarica JRM ( English : Yugoslavia war navy ) Yugoslav Navy 1969 -- 1992 Ratna Mornarica Vojske Jugoslavije RМVЈ ( English : War navy of Yugoslavia Armed Forces ) 1992 -- 2003 RTOP Raketna Topovnjača or Ракетна Топовњача ( English : Rocket gunship ), named by Yugoslavia peoples heroes RČ Raketni Čamac or Ракетни Чамац ( English : Rocket boat ), 1969 -- 1992, named by Yugoslavia peoples heroes VPBR Veliki Patrolni Brod or Велики Патролни Брод ( English : Big patrol ship ), 1969 -- 1992, named by Yugoslavia coastal towns TČ Torpedni Čamac or Торпедни Чамац ( English : Torpedo boat ), 1969 -- 1992 PČ Patrolni Čamac or Патролни Чамац ( English : Patrol boat ), 1969 -- 1992, named by mountains PO Pomoćni Oružar or Помоћни Оружар ( English : Auxiliary аrmourer ), 1969 -- 1992 RML Rečni minolovac or Речни миноловац ( English : River minesweepers ), 1969 -- 1992, named by places of WWII battles RPB Rečni patrolni brod or Речни патролни брод ( English : River patrol boat ), 1969 -- 1992 Podmornica or Подморница ( English : Submarine ), 1969 -- 1992, named by rivers or human qualities RЕ Razarač Eskortni or Разарач Ескортни ( English : Escort destroyer ), 1969 -- 1992 PT Pomoćni transportni or Помоћни транспортни ( English : Auxiliary transport ), 1969 -- 1992 DČ Desantni čamci or Десантни чамци ( English : Landing craft ), 1969 -- 1992 Prefix conventions The designations for United Kingdom ships applied at the time of the British Empire, before the establishment of separate navies for the Dominions. In the Royal Netherlands Navy, `` HNLMS '' is the prefix in English, a translation of the Dutch original `` Hr.Ms. '' or `` Zr.Ms. ''. `` Hr.Ms. '' should preferably not be used in English - language documents ; nevertheless it is often seen on the World Wide Web. Until the moment a Dutch naval ship officially enters active service in the fleet, the ship 's name is used without the prefix. Since King Willem - Alexander succeeded Queen Beatrix on 30 April 2013, `` Hr.Ms. '' is replaced by `` Zr.Ms. ''. In Australia, the prefix NUSHIP is used to denote ships that have yet to be commissioned into the fleet. In the United States, all prefixes other than `` USS '', `` USNS '', `` USNV '', and `` USRC '' were made obsolete in 1901, when President Theodore Roosevelt issued an Executive order fixing American naval nomenclature. USRC was replaced by USCGC when the Revenue Cutter Service merged with the United States Lifesaving Service to become the United States Coast Guard in 1915. USLHT also was replaced by USCGC when the United States Lighthouse Service became a part of the U.S. Coast Guard in 1939. USC&GS was replaced by NOAAS when the United States Coast and Geodetic Survey merged with other U.S. Government scientific agencies to form the National Oceanic and Atmospheric Administration in 1970. A United States Navy ship that is not in active commission does not hold the title of United States Ship with simply the name without prefix used before and after commissioned service. Vessels, such as yard and harbor craft that are not commissioned and `` in service '' are officially referred to by name or hull number without prefix. Military Sealift Command ( MSC ) civilian manned ships `` in service '' are given the prefix United States Naval Ship ( USNS ). Prior to commissioning, ships may be described as a pre-commissioning unit or PCU ; for example, the uncommissioned Gerald R. Ford ( CVN - 78 ) has been described as the `` pre-commissioning unit ( PCU ) Gerald R. Ford. '' However, the vessel 's official name is Gerald R. Ford without any prefix, and will be known as USS Gerald R. Ford once commissioned. When it is stricken from the fleet list, a ship typically has the prefix `` ex - '' added to its name, to distinguish it from any active ships bearing the same name. For example, after USS Constellation ( CV - 64 ) was retired in 2003, she became referred to as ex-Constellation. Note that while calling a US ship `` the USS Flattop '' may make grammatical sense, the preliminary article `` the '' is discouraged by nearly all style guides, and the U.S. Navy. The U.S. Navy uses ship names without article, except for USS The Sullivans, named for the five Sullivan brothers, all lost at sea during World War II. Its British equivalent ( `` the HMS Flattop '' ) is also discouraged, since `` the Her Majesty 's Ship '' would be grammatically incorrect. Yugoslavia war navy had strict naming rules and ships prefix that was driven by order by President of Socialist Federal Republic of Yugoslavia in 1969. After dissolution of Socialist Federal Republic of Yugoslavia new state Federal Republic of Yugoslavia continued same naming convention for War navy of Yugoslavia Armed Forces from 1992 to 2003. In science fiction Fictional equivalents of tri-letter prefixes frequently appear in English - language science fiction works, applied to seafaring and spaceborne ships alike. See also Space navy for similar adoption of naval customs for fictional spacefaring military organizations. Star Trek -- the United Federation of Planets uses the prefix `` USS '' for its starships. While Gene Roddenberry never defined what the abbreviation stood for, some speculate that it means `` United Space Ship '', `` United Star Ship '', or `` United ( Federation of Planets ) Starfleet Starship / Ship ''. In the alternate `` Mirror Universe '', the Terran Empire use an `` ISS '' prefix instead. Other races use different prefixes for their ships : Klingons use IKS ( Imperial Klingon Ship ) or IKC ( Imperial Klingon Cruiser ). Romulan vessels typically receive the prefix IRW ( Imperial Romulan Warbird ), or RIS where some speculate that it means `` Romulan Imperial Ship '', and ChR. ( ChR is from novelist Diane Duane 's imagining of the Star Trek Universe, in which the Romulans refer to their home planet as `` Ch'Rihan ''. Though Duane 's version has a loyal following among many fans, it is not considered official Star Trek canon ; similarly, the Ferengi designation of FMS, and the Cardassian CDS, are also not canon. ) Babylon 5 -- The Earth Alliance uses the prefix `` EAS '' for `` Earth Alliance Ship ''. Some fan material also uses it for `` Earth Alliance Station ''. Elite : Dangerous -- The Federation uses the prefix `` FNS '' ( Federal Naval Ship ) for some military ships. The Empire uses `` INV '' ( Imperial Naval Vessel ). Firefly -- Vessels in the Union of Allied Planets fleet are given the prefix `` IAV '', for Interstellar Alliance Vessel. The Terran Confederation, from Wing Commander, uses TCS ( Terran Confederation Ship ) for its vessels. Halo -- United Nations Space Command spacecraft use the prefix `` UNSC ''. Mass Effect -- features several prefixes, primarily `` SSV '' for `` Systems Alliance space vehicle '' and `` MSV '' for `` Merchant Space Vehicle '', used on numerous human commercial ships, as well as `` PFS '' for a Turian Hierarchy naval craft, and a freighter AML Demeter of unknown affiliation. Dead Space -- `` USG '', standing for `` United Spacefaring Guild '', which oversees civilian spacecraft operation, including the planet - cracker class leader USG Ishimura of the Concordance Extraction Corporation ; `` USM '' for the Earth Defense Force of EarthGov ; and `` CMS '' for its former opponents, the Sovereign Colonies Armed Forces. StarCraft : Brood War -- The United Earth Directorate uses DSS ( presumably for Directorate Space Ship, e.g. DSS Aleksander ) ; the Terran Confederacy used CSF ( Confederate Space Fleet, e.g. CSF Ragnorak ) for their battlecruisers. Killzone -- The Interplanetary Strategic Alliance ( ISA ) uses `` ISC '', for Interplanetary Strategic Cruiser. The Moon is a Harsh Mistress -- The Federated Nations use `` FNS '', presumably meaning `` Federated Nations Ship ''. Alien -- The ships use prefix `` USCSS '' for `` United States Cargo SpaceShip '' in Nostromo, Prometheus or Covenant. The Lost Fleet -- The Alliance use the prefix `` ASN '' for `` Allied Systems Navy '' ( or possibly `` Alliance of Systems Navy '' ), the Syndicate Worlds do not use prefixes. CoDominium -- CoDominium vessels use the prefix `` CDS '' for CoDominium Ship. `` Honorverse '' -- The Manticoran kingdom uses `` HMS '' as a prefix, the Graysons use GNS, and the Havenite ships use `` PNS '' being reflections of actual ship prefixing traditions, and mirroring the Napoleonic wars. The Culture -- Ships are identified by a three - letter prefix denoting class ( such as GSV for `` General Systems Vehicle '' or ROU for `` Rapid Offensive Unit '' ), followed by their personal name. The Expanse -- Ships of the United Nations Navy use the prefix `` UNN, '' while ships of the Martian Congressional Republic Navy are prefixed with `` MCRN ''. The Nauvoo, a generation ship commissioned by the Church of Latter Day Saints was prefixed with `` LDSS '' for `` Latter Day Saints ' Ship '', and later changed to `` OPAS '' and re-christened as the `` OPAS Behemoth '' representing the Outer Planets Alliance. Unreal Tournament -- Ships mentioned there have prefixes such as ITV ( `` Interstellar Transport Vessel '', the first non-tutorial match in the tournament happens on board of ITV Oblivion ) and ISV ( `` Interstellar Science Vessel '', ship 's name being ISV - Kran from Unreal ). Unreal : Return to Na Pali -- ISV ( ISV - Kran ) and UMS ( `` Unified Military Services '', a prefix for warships ). References Notes ^ Jump up to : Naval History And Heritage Command. ^ Jump up to : `` Maritime Acronyms and Abbreviations ''. Royal Institution of Naval Architects. Archived from the original on 19 August 2016. Jump up ^ `` '' Dead Vessel '' Doctrine ``. USLegal.com. US Legal, Inc. Retrieved 7 February 2015. ^ Jump up to : `` SHIP PREFIX -- GLOSSARY -- CONTINUED ''. richatlanticinterserv.com. Rich Atlantic International Services. Archived from the original on 5 August 2012. Retrieved 7 February 2015. Jump up ^ `` Submarine and Special Warfare Support Vessel ''. Military Sealift Command. Retrieved 3 December 2010. Jump up ^ ( 1 ) Ships of CalMac website Jump up ^ Royal Australian Navy. `` MSA Brolga ''. navy.gov.au. Retrieved 23 September 2015. Jump up ^ `` About the Coast Guard ''. 4 September 2008. Archived from the original on 17 July 2010. Retrieved 21 March 2010. Jump up ^ `` Russian and Soviet Navy Battleships ''. frontier.com. Retrieved 23 September 2015. Jump up ^ `` List of Acronyms Preceding the Name of a Ship ''. 22 March 2010. Retrieved 22 March 2010. Jump up ^ Habesch, The Army 's Navy, p. 154 Jump up ^ Naval Undersea Warfare Center ( NUWC ) ( July 25, 2012 ). `` Dry Dock and overhaul of USNV Battle Point YTT - 10 ''. Navy Electronic Business Opportunities. Retrieved 7 April 2015. Jump up ^ Circulaire Zeemacht 1569cc ( 1988 ). Jump up ^ Dasgupta, Soumyajit. `` What are Ship Prefixes for Naval and Merchant Vessels ? ''. Retrieved 25 August 2014. Jump up ^ United States Coast Guard Historian 's Office. Jump up ^ `` PCU Gerald R. Ford ( CVN 78 ) Welcomes 60 New Crew Members '' ( Press release ). Navy News Service. 6 June 2013. NNS130606 - 12. Retrieved 24 July 2016. Jump up ^ http://www.the-sullivans.navy.mil/ Jump up ^ In - Game Codex, entry for SSV Normandy. Sources Naval History And Heritage Command. `` Ship Naming in the United States Navy ''. Naval History And Heritage Command. Retrieved 7 April 2015. United States Coast Guard Historian 's Office ( 5 January 2015 ). `` Coast Guard History ''. Frequently Asked Questions. United States Coast Guard. Retrieved 7 April 2015. External links Warship National Prefixes Retrieved from `` https://en.wikipedia.org/w/index.php?title=Ship_prefix&oldid=854178661 '' Categories : Ship prefixes Hidden categories : Articles with short description Articles needing additional references from January 2009 All articles needing additional references All articles with unsourced statements Articles with unsourced statements from January 2016 Articles containing French - language text Articles with unsourced statements from February 2018 Use dmy dates from November 2010 Talk Contents About Wikipedia Dansk Deutsch Español Français 한국어 Hrvatski Italiano Nederlands 日本 語 Norsk Norsk nynorsk Polski Português Suomi Türkçe 6 more Edit links This page was last edited on 9 August 2018, at 13 : 52 ( UTC ). About Wikipedia

Question: what does s s stand for on a boat
Answer: Single-screw Steamship