A "snotter" or as some more fastidious sailors may refer to as a "snouter" or "snorter" has nothing to do with your nose or anything goopy. It is used to set the tension on the spar (or spirit) of a spritsail by pulling the lower end of the spar towards the mast. This governs how the sail is set. Because there is a wide variation in boats with spritsails, there is a wide range of variation in how the snotter gets rigged. In most small spritsail-rigged sailboats, it is simply hooked onto the lower end of the spirt spar and then secured to the mast. The origin of the term is obscure.

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