What is an instrument for measuring angles (generally called a quadrant), having an arc which measures up to 9Oº, but being itself the eighth part of a circle. Cf. Sextant called?

octant — An instrument for measuring angles (generally called a quadrant), having an arc which measures up to 9Oº, but being itself the eighth part of a circle. Cf. Sextant. (Webster's 1913.)

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