# Ship naming conventions **URL:** \ **Category:** Factual Questions\ **Created:** [November 5, 2002, 8:50pm UTC](https://boards.straightdope.com/t/ship-naming-conventions/135432 "2002-11-05T20:50:19Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Whiner](https://avatars.discourse-cdn.com/v4/letter/w/bc8723/32.png) [@Whiner](https://boards.straightdope.com/u/Whiner)\ **Post date:** [November 5, 2002, 8:50pm UTC](https://boards.straightdope.com/t/ship-naming-conventions/135432/1 "2002-11-05T20:50:19Z")
A cursory Google and Straight Dope archive search did not turn up the answer to this one. What does the “SS” mean in the beginning of a ship’s name? I (think I) know that HMS is His/Her Majesty’s Service. No one in the office knows either. ---
**Author:** ![KCB615](https://avatars.discourse-cdn.com/v4/letter/k/ea666f/32.png) [@KCB615](https://boards.straightdope.com/u/KCB615)\ **Post date:** [November 5, 2002, 9:02pm UTC](https://boards.straightdope.com/t/ship-naming-conventions/135432/2 "2002-11-05T21:02:52Z")
SS = Steam Ship HMS = His/Her Majesty’s Ship And just in case… USS = United States Ship MV = Motor Vessel ---
**Author:** ![tomndebb](https://avatars.discourse-cdn.com/v4/letter/t/b9e5f3/32.png) [@tomndebb](https://boards.straightdope.com/u/tomndebb)\ **Post date:** [November 5, 2002, 10:38pm UTC](https://boards.straightdope.com/t/ship-naming-conventions/135432/3 "2002-11-05T22:38:30Z")
Most commercial designations are simply two characters: SS and MV, as **KCB135** noted. Most military and scientific designations have more letters: HMS and USS, of course, but also (in WWII) IJS (Imperial Japanese Ship _anglicized, of course_), DKM (_Deutsches Kriegs Marine_), HMCS (His/Her Majesty’s Canadian Ship), etc. Currently, some U.S. Naval support ships are identified USNS, **C** oast **G** uard cutters are labeled US **CG** and other specialty ships, such as oceangraphic research or mapping have really long letter strings that spell out what they do: NOAA Ship, etc. There have also been a few other codes used. The Titanic was an SS, except that the White Star line had the contract to haul the British Royal Post, so she got to use the RMS (Royal Mail Ship) designation. The preceding codes should not be confused with the function codes applied by many navies. For example, the battleship USS New Jersey is designated BB-62 and the aircraft carrier USS Enterprise is designated CVN-65, where BB indicates battleship and CVN indicates nuclear powered aircraft carrier. ---
**Author:** ![Milton\_De\_La\_Warre](https://avatars.discourse-cdn.com/v4/letter/m/e480ec/32.png) [@Milton\_De\_La\_Warre](https://boards.straightdope.com/u/Milton_De_La_Warre)\ **Post date:** [November 7, 2002, 2:56pm UTC](https://boards.straightdope.com/t/ship-naming-conventions/135432/4 "2002-11-07T14:56:05Z")
US Coast Guard ships are USCGC (United States Coast Guard Cutter). They also define “ship” differently than most others, who (IIRC) say the difference between a ship and a boat is that the former are 175 feet or more in length. The USCG says some smaller vessels in its service are also “ships”, though I don’t know exactly what their cutoff is. I believe their 44 foot vessels are still only “boats”; as AFAIK they are not named and only hull-numbered. ---
**Author:** ![Milton\_De\_La\_Warre](https://avatars.discourse-cdn.com/v4/letter/m/e480ec/32.png) [@Milton\_De\_La\_Warre](https://boards.straightdope.com/u/Milton_De_La_Warre)\ **Post date:** [November 7, 2002, 3:23pm UTC](https://boards.straightdope.com/t/ship-naming-conventions/135432/5 "2002-11-07T15:23:03Z")
Also, German ships of the Kaiser’s time were SMS (Seine Majestat’s Schiff = His Majesty’s Ship). ---
**Author:** ![audit1](https://avatars.discourse-cdn.com/v4/letter/a/ed8c4c/32.png) [@audit1](https://boards.straightdope.com/u/audit1)\ **Post date:** [November 7, 2002, 3:48pm UTC](https://boards.straightdope.com/t/ship-naming-conventions/135432/6 "2002-11-07T15:48:10Z")
The difference between a USS (United States Ship) and a USNS (United States Naval Ship) is A USS is Us Navy crew (for example USS ENTERPRISE) while a USNS is Civillian manned (the transport USS BOB HOPE).