Definitions for sternpostˈstɜrnˌpoʊst
Random House Webster's College Dictionary
an upright member rising from the after end of a keel; a rudderpost or propeller post.
Category: Nautical, Navy
Origin of sternpost:
(nautical) the principal upright timber at the stern of a vessel
A timber or steel bar extending from the keel to the main deck at the stern of a vessel.
a straight piece of timber, or an iron bar or beam, erected on the extremity of the keel to support the rudder, and receive the ends of the planks or plates of the vessel