1. of, relating to, or located at the nadir
Usage: astronomy; technical

Examples

• The nadiral point lies directly opposite the zenith in the celestial sphere.
• Astronomers measured the nadiral distance of the star from Earth.
• The satellite’s nadiral view provided a clear image of the ground below.
• Navigation requires understanding both zenithal and nadiral coordinates.
• The nadiral position marked the lowest point in the sky from the observer’s perspective.