What is (a) A kind of triangular lyre or harp. (b) A kind of game at ball played by three persons standing at the angular points of a triangle called?

trigon — (Gr. & Rom. Antiq.) (a) A kind of triangular lyre or harp. (b) A kind of game at ball played by three persons standing at the angular points of a triangle. (Webster's 1913.)

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