Mast
The mast was the vertical spar of a sailing vessel used to carry horizontal spars (yards) so that sails could be mounted to the vessel. Sailboats typically have a single mast, while other large vessels may have several masts, such as a two-masted , or a three-masted clipper ship. 

When recalling the story of the Sirens, Harry Kim explained to Neelix that the only way Odysseus' ship could get past them and not succumb to the Siren calls, was that Odysseus told his crew to cover their ears as he remained tied to the mast of the ship, so that he could listen himself without being led astray. ()

While sailing the Bajoran system in a Bajoran lightship in 2371, Benjamin Sisko noted that the ship had experienced damage when one of the mast supports gave way, causing the starboard sprit to foul one of the main sails. ()

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