Course (sail)

In sailing, a course is the lowermost sail on a mast.

This term is used predominantly in the plural to describe the lowest sails on a square rigged vessel, i.e., a ship's courses would be the foresail, mainsail, and, on the rare occasions in which one is shipped, mizzen.Gaff-rigged vessels may use the term (for the lowest sail rigged aft of each mast), but are more likely to refer simply to a mainsail, foresail, etc. A Bermuda- or lateen-rigged yacht, whether sloop, cutter, ketch or yawl, would not usually be described as having a course.

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