octant

Noun

WordNet 3.0

Noun (1)

  1. a measuring instrument for measuring angles to a celestial body; similar to a sextant but with 45 degree calibration
Advertisement

Webster's Dictionary (GCIDE)

Octant \Oc"tant\, n. [L. octans, -antis. fr. octo eight. See Octave.]

1.(Geom.) The eighth part of a circle; an arc of 45 degrees. [1913 Webster]

2.(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. [1913 Webster]

3.An instrument for measuring angles (generally called a quadrant), having an arc which measures up to 9O[deg], but being itself the eighth part of a circle. Cf. Sextant. [1913 Webster]

4.(Math. & Crystallog.) One of the eight parts into which a space is divided by three coordinate planes. [1913 Webster]

Advertisement