Webster's English Dictionary

Enter the word to look up:

nadir

na.dir \'na--.di(*)r, 'na-d-*r\ n [ME, fr. MF, fr. Ar nazsub-dot>i-r 
   opposite] 1: the point of the celestial sphere that is directly opposite 
   the zenith a nd vertically downward from the observer 2: the lowest point