IPA: //ˈæstɑːrbɔrd//
KK: /æstærbɔrd/
In the direction of the right side of a ship when facing forward.
The captain ordered the crew to steer astarboard to avoid the rocks.
Astarboard is derived from the Old English "æstar" (meaning east) and "bord" (meaning side of a ship). The term originally referred to the side of a ship that was on the right when facing forward, which is associated with the direction of the rising sun in the east.
Think of the word 'east' ('æstar') to remember that 'astarboard' refers to the right side of a ship when facing forward.