In the early days, mariners initially called the…

In the early days, mariners initially called the right side of the ship the ‘steering side’ or ‘steerboard.’ The strange names arose because most sailors were right-handed, and the majority of vessels had steering oars on the right side of the stern.
Over time, the ‘steering side’ turned into stēorbord,’ which is a combination of Old English stéor (‘steering oar’) and bord (‘side of the boat’). Old English stēorbord also meant ‘the rudder side,’ as the Teutonic peoples steered their sailboats with a paddle on the right side of a boat.
The word port is not an original term either, as sailors previously used “larboard” to describe the left side of the ship. Stemming from Old English bæcbord, the word larboard references the ‘loading side’ of the ship. And since the loading side was opposite of the oar, the term naturally describes the left side of the boat.
Sailors soon realized how “larboard” was too similar to “starboard” and decided to use the word port, instead. Considering how the left side is port-facing, the transition to port makes sense. Even more serendipitous is how the word “port” already stems from Latin portus for ‘haven’ or ‘harbor.’
The convenient shift took place in Old English and stuck around through Middle English and Old French. But it wasn’t until the 19th century that the United States and British Navy officially replaced “larboard” with “port.” As documented by the General Order of February 18, 1846, George Bancroft announced: “… in consequence of the similarity of sound, the word ‘Port’ is hereafter to be substituted for ‘Larboard.’”
MILITARY HISTORY SOCIETY OF ROCHESTER
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