Spritsail
A spritsail or sprit was a component in a Bajoran lightship. They, along with the other sails, captured ions in order to propel the ship.

During his voyage to prove lightships were spaceworthy, Benjamin Sisko was forced to jettison a sprit from his lightship after the mast support gave way. This dampened his spirits, but Jake urged him to push on. ()

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Propulsion technology