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octant

英 ['?kt(?)nt] 美['ɑkt?nt]
  • n. [航][水運(yùn)] 八分儀；[數(shù)] 八分圓；成45°視角的位置

英文詞源

octant (n.)
instrument for making angular measurements in navigation or astronomy, 1731, from Late Latin octans "the eighth part," from octo "eight" (see octa-) on analogy of quadrant. In geometry, octant meant "the eighth part of a circle."