What is a small boom, pole, or spar, which crosses the sail of a boat diagonally from the mast to the upper aftmost corner, which it is used to extend and elevate called?

sprit — A small boom, pole, or spar, which crosses the sail of a boat diagonally from the mast to the upper aftmost corner, which it is used to extend and elevate. (Webster's 1913.)

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