n.
Pronunciation: ' n ā - ˌ dir, ' n ā -d ə r
Function: noun
Etymology: Middle English, from Middle French, from Arabic na ḍ h ī r opposite
Date: 15th century
1 : the point of the celestial sphere that is directly opposite the zenith and vertically downward from the observer
2 : the lowest point
nadir 1: 1 nadir, 2 observer, 3 zenith