World Library  
Flag as Inappropriate
Email this Article

Port (nautical)

Article Id: WHEBN0000202710
Reproduction Date:

Title: Port (nautical)  
Author: World Heritage Encyclopedia
Language: English
Subject: Hull (watercraft), Battle of the River Plate, USS Indianapolis (CA-35), Doppler radar, USS Atik (AK-101), Lifting body, Gordon Chung-Hoon, Vasa (ship), USS Texas (1892), USS Cole (DDG-67)
Publisher: World Heritage Encyclopedia

Port (nautical)

Port and starboard are nautical terms which refer to the left and right sides, respectively, of a ship as perceived by a person on board facing the bow (front). At night, the port side of a vessel is indicated with a red navigation light and the starboard side with a green one.

The starboard side of most naval vessels the world over is designated the "senior" side. The officers' gangway or sea ladder is shipped on this side and this side of the quarterdeck is reserved for the captain. The flag or pennant of the ship's captain or senior officer in command is generally hoisted on the starboard yard.


Starboard (right)

The origin of the term starboard comes from early boating practices. Before ships had rudders on their centrelines, they were steered by use of a specialized steering oar. This oar was held by an oarsman located in the stern (back) of the ship. However, similar to now, there were many more right-handed sailors than left-handed sailors. This meant that the steering oar (which had been broadened to provide better control) used to be affixed to the right side of the ship. The word starboard comes from Old English steorbord, literally meaning the side on which the ship is steered, descendant from the Old Norse words stýri meaning "rudder" (from the verb stýra, literally "being at the helm", "having a hand in") and borð meaning etymologically "board", then the "side of a ship".

Port (left)

An early version of "port" is larboard, which itself derives from Middle-English ladebord via corruption in the 16th century by association with starboard. The term larboard, when shouted in the wind, was presumably too easy to confuse with starboard[1] and so the word port came to replace it. Port is derived from the practice of sailors mooring ships on the left side at ports in order to prevent the steering oar from being crushed.

Larboard continued to be used well into the 1850s by whalers, despite being long superseded by "port" in the merchant vessel service at the time. "Port" was not officially adopted by the Royal Navy until 1844 (Ray Parkin, H. M. Bark Endeavour). Robert FitzRoy, captain of Darwin's HMS Beagle, is said to have taught his crew to use the term port instead of larboard, thus propelling the use of the word into the Naval Services vocabulary.


Before modern standardization, quartermasters were advised to follow the rotation of the bottom of the wheel. Thus, when obeying a "hard a-starboard" command, the QM would turn the bottom of the wheel to the right, or starboard. This applied the left rudder and the ship turned to its left, or to port. Steering with the bottom of the wheel was apparently an approved way to learn helming more than a century ago.

The nautical reason for a "hard a-starboard" command to turn left seems related to the tiller and not the rudder. A tiller is pushed to the right, or starboard, to apply left rudder and turn the vessel to the left.

Right-of-way for other vessels

Vessels at sea do not actually have any "right-of-way"—they may be, correctly, in the position of being the "stand-on vessel" or the "give-way" vessel. Therefore, at no time should any vessel actually navigate its way into a collision, and the regulations are clear that no one in command of a vessel may assume a "right-of-way" up to a point of collision.

Consider two ships on courses that intersect. The ordinary rule is that the ship on the left must 'give way'. The stand-on vessel (right) sees the green light on the starboard (right) side of the ship on the left i.e., 'give-way vessel' (left). The 'give-way vessel' (left) sees the red light on the port side of the 'stand-on vessel' (right). If the courses are intersecting, the helmsman usually gives way to a red light by going around the stern of the stand-on vessel.

There are other rules governing which is a stand-on vessel, such as the wind based rules for sailing vessels, powered ships giving way to sailing ships, and all other ships giving way to powered vessels that are constrained by their draft or restricted in their ability to maneuver. Therefore the green light does not mean an unqualified go, but rather it means proceed with caution subject to other rules applying. The earliest railway signals went red/green/white (as per the stern light) for stop/caution/go following this naval practice and were only later changed to the more familiar red/yellow/green.

The very simple application of red light and green light is to remember the rhyme "If to starboard red appear, 'tis your duty to keep clear" meaning that if the helmsman sees a red light on his starboard side he is the give-way vessel. The sailing rule that dictates that a sailing vessel on starboard tack is the stand-on vessel is as old as any other regulation. Likewise, if on the same tack, a sailing vessel that is upwind of another is the give-way vessel.


Sidelights are lit on the port and starboard side on vessels at night to indicate starboard bow with a green light, and port bow with a red light, each lit from right ahead to 22.5 degrees abaft the beam on its respective side. In international waters, the lighting of vessel is standardized in §23 Part C COLREG.

Mnemonic devices

There are a number of tricks used to remember which side port and starboard each refer to:

  • A ship that is out on the ocean has "left port".
    • The sailor left port with a red nose.
  • Port and left both contain four letters.
  • "Port wine is red; so is the port light."
  • "Port is not right for children" (Port wine is red and not being "right for children" is therefore "left".)
  • The phrase "Any red port left in the can?" can be a useful reminder. It breaks down as follows:
    • The drink port is a fortified red wine—which links the word "port" with the color red, used for navigational lights (see below).
    • "Left" comes from the phrase and so port must be on the left.
    • The reference to "can" relates to the fact that port-hand buoys are "can"-shaped.
  • A variation on the above is "Two drops of red port left in the bottle."
  • Another variation: "Port is the red wine that is left in the glass."
  • The common abbreviation P.S. (for English postscript, derived from Latin post scriptum) can be viewed as port ("left") and starboard ("right").
  • "Star light, star bright, starboard is to the right."
  • "There is no red port wine left".
  • Terms referring to the right side are longer words ("starboard", "right", and "green"), while terms referring to the other side are shorter words ("port", "left", and "red").
  • Starboard contains two letter "R"s, compared to only one in port; therefore, starboard refers to the right side.
  • Red is the representative color for some major ideologies of the political Left, e.g. socialism or communism; whereas green is the color of US cash and is often synonymous with wealth.
  • In countries that drive on the left side of the road: If someone is drinking Port, they should be on the passenger side; the "star" of the boat, or person who is in control of the boat, is on the driver's side.
  • Port and starboard are in alphabetical order, which can be associated in European languages with reading from left to right. So they are in the same order as reading text. Left and right are in the same order.
  • Green has two E's, Starboard has two R's, so starboard, green right.


A port buoy is a lateral buoy used to guide vessels through channels or close to shallow water. The port buoy is one that a vessel must leave to port when passing upstream. If in International Association of Lighthouse Authorities area A, the port buoys are red. If in IALA area B (Japan, the Americas, South Korea, and the Philippines) then the "handedness" of buoyage is reversed, and a vessel leaves black or green buoys to port.

Mnemonic devices for buoys in IALA area B:

  • Best People On Earth = "Black Port on Entering"
  • RRR = Red Right Returning

See also


Further reading

  • Herreshoff, Halsey, (consulting editor) (1983) The Sailor’s Handbook, Little Brown and Company
  • Jobson, Gary (1987) Sailing Fundamentals, Simon & Schuster
  • Maloney, Elbert S., (editor) (1999) Chapman Piloting: Seamanship & Small Boat Handling, Hearst Marine Books, New York
  • Rousmaniere, John (1999) The Annapolis Book of Seamanship, Simon & Schuster
  • Seidman, David (1995) The Complete Sailor, International Marine

External links

  • The origins of 'port' and 'starboard' at the UK National Maritime Museum websitean:Babor

ca:Babord da:Bagbord de:Backbord et:Pakpoord eo:Babordo fr:Bâbord it:Babordo#B ja:取舵 no:Babord nn:Babord nds:Backboord sv:Babord zh:左舷及右舷

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from World eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.