Sternpost
Vertical structure at the aft of a boat From Wikipedia, the free encyclopedia
A sternpost is the upright structural member or post at the aft end of a ship or a boat,[1][2] to which are attached the transoms and the rearmost part of the stern.[3]

The sternpost may either be completely vertical or may be tilted or "raked" slightly aft.[4] It rests on or "fays to" the ship's keel.[1]
Traditionally, the rudder was suspended from the sternpost, and the propellers descended from it.[1][2] With changes in how these are positioned, in modern shipbuilding vessels are often not considered to have a sternpost.[1]
See also
Look up sternpost in Wiktionary, the free dictionary.
References
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