SS Boat Meaning: Understand This Ship Prefix | LakeWizard

You may have probably come across a boat or ship with the SS prefix. So, what’s the SS boat meaning? This article has the answers.

The SS prefix in boats is quite common. And most people tend to confuse it with different water vessels. So, what does it mean when a boat has an SS prefix before its name?

The SS prefix in boats refers to single-screw ships. A single screw ship comes with a single-screw propeller, making it distinct from water vessels that come with a double screw propeller. It was originally used to refer to steamships. But, steamships are obsolete these days.

In this article, we will explore what the SS prefix in boats refers to. We will also take a closer look at some common ship prefixes, potentially confusing prefixes as well as other ship prefixes that you may come across.

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If you have paid closer attention to boats, you may have probably noticed that they come with letters. These letters usually appear before the boat’s name. At first glance, these letters may appear random. But the reality is, these letters usually indicate the purpose of the boat, thus providing easier identification.

In most cases, the prefixes or the letters are usually displayed on the boat’s hull. This is specifically done for convenience. And the SS prefix is one such designation. So, what does this designation imply? We will take a closer look at this designation.

Common Ship Prefixes

As mentioned above, the prefixes that you will see on a boat mainly serve the purpose of identifying its purpose. And while different countries use different naming conventions, the U.S and the U.K share similar naming conventions.  Some of the most commonly used ship prefixes include:

  • Fishing Vessel – FV
  • Royal Mail Ship – RMS
  • Gas Turbine Ship – GTS
  • Platform Supply Vessel – PSV
  • Motor Ship – MS
  • Motor Vessel – MV
  • Sailing Vessel – SV
  • Life Boat – LB
  • Training Ship – TS
  • Nuclear Ship – NS
  • Motor Tanker – MT
  • Research Vessel – RV

SS Boat Meaning

As you can see, it’s easy to identify a boat’s purpose, just by looking at the prefixes before its name. But, this is not always the case with SS. A couple of years back, SS used to refer to steamships only. However, things have changed considerably over the last couple of years, in terms of the propulsion method.

Today, SS boat may refer to a steamship or a single-screw ship. So, what exactly does it mean when a boat is called a single-screw ship? A single-screw ship is more of a propulsion method, which is more like the steam propulsion method.

So, if you happen to come across a boat with the SS prefix before its name, it’s highly likely that the boat is a single-screw ship and not necessarily a steamship. As you may expect, steamships are rare these days.

Potentially Confused Prefixes

The SS boat designation is usually confused with other prefixes, especially for boats that bear the same letters. One of the most common prefixes that the single-screw ship is confused with is the sailing ship or SS. As you can see, these two boats bear identical prefixes. However, the proper prefix for the sailing ship is SV or sailing vessel.

Another commonly confused prefix with the SS boat is the USS. But, you should note that a boat with a USS designation is not in any way related to one that has a SS designation. USS simply means United States Ship. And as mentioned earlier, SS means single-screw ship. As you can see, these two boats may not be related in any way, as much as their prefixes may appear similar.

Other Boat Naming Prefixes

Apart from SS, you may also come across various other prefixes on different water vessels. Some of the most popular boat naming prefixes that you may come across include:

Merchant Vessel – MV

A merchant vessel or MV refers to a ship or boat that’s mainly commercial. Such ships or boats are usually used for moving around people or transporting goods. Merchant vessels are also known as trading vessels or TVs. The main purpose of ships with this designation is to transport people or goods, for payment. The MV designation helps to separate them from other vessels that may be moving people or goods around.

For instance, cruise ships and private boats also move people around. But, they usually don’t come with the MV designation, since they are mainly designed for leisure or relaxation not purely commercial.

Paddle Steamer – PS

Another prefix that you may come across is PS. The PS designation refers to paddle steamers. Paddle steamers are mainly propelled by steam. However, boats or ships propelled by steam are not common these days. Hence, it will take you quite some time before you see a boat or ship with the PS designation.

Research Vessel – RV

The RV designation refers to research vessels. So, if you happen to come across a boat or a ship with this prefix, then you should know that it’s mainly used for research purposes. Research vessels can be used for various research-related work including fisheries, oceanographic, polar, naval and oil exploration, just to name a few.

Platform Support Vessel – PSV

PSV or platform support vessel is a ship, boat or any other water vessel, which serves the purpose of supplying offshore gas and oil platforms. Such ships are used to bring in and take out supplies needed for the efficient running of these platforms.

Deep Submerged Vessel – DSV

Also called a deep submerged vessel or a diving support vessel, the main role of a DSV is to provide a diving base or related projects for professional divers across the globe.

Wrapping It Up

The SS prefix in boats no longer has to confuse you. It simply refers to a single screw ship. Hence, if you ever happen to come across this designation, then you now know what it means.


Brian Samson

Brian Samson

I have a deep love of houseboating and the life-changing experiences houseboating has brought into my life. I’ve been going to Lake Powell on our family’s houseboat for over 30 years and have made many great memories, first as a child and now as a parent. My family has a passion for helping others have similar fun, safe experiences on their houseboat.

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