Bowstrut
If it's above the surface, attached to the rigging, it's a bowsprit. If it's below the surface, it's a ram. More commonly found on rowing ships, triremes and such.
it means to depart the ship
The Figurehead
It is a spar. Though it is usually called a health spar, to differentiate it from a spar in the rigging on a ship, or a spar town (the spar town of Bath, England is one example).
Since the definition of spar is a pole that supports the sail of a ship or boat, the antonyms of spar are the antonyms of the synonyms of spar. Some synonyms are rod, rail, and varnish.
yardarm
mast-a vertical spar to support sails on a ship
Used as a verb, it can mean to fight in practice (I'm going to spar with my boxing trainer) As a noun, a part of the mast and rigging of a sailing ship that holds the sails (During the storm, the wind broke a spar.)
The jack is the spar pole on the bow of a ship, where the Union Jack or other Jack (a type of flag is flown).
The early submarine (the Turtle) had a screw device to drill into the ship, and a "time bomb" explosive spar (torpedo, mine) that would be attached to the hull below water.
This could be a tree's limb or a ship's spar.
The vertical pole is the mast and the horizontal pole is the spar. Unless you are referring to a Polish sailor.