What does "octant" mean?

Octant: (Astron. & Astrol.) The position or aspect of a heavenly body, as the moon or a planet, when half way between conjunction, or opposition, and quadrature, or distant from another body 45 degrees.

Additional senses

  1. 2.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.
  2. 3.(Math. & Crystallog.) One of the eight parts into which a space is divided by three coördinate planes.

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