Zenith & Nadir

Zenith & Nadir

Zenith

  1. The point on the Celestial Sphere directly above the observer. The zenith is diametrically opposite to the nadir.
  2. In general, the highest state or point.
Originally derived from the Arabic semt ar-ras meaning way over the head: ME senyth; ML cenit.

Source: Ba-1418.

Nadir

  1. The point on the Celestial Sphere directly below the observer. The nadir is diametrically opposite to the zenith.
  2. In general, the lowest state or point.
Originally derived from the Arabic nazir meaning the corresponding opposite.

Source: Ba-806.