/zee"nith/ or, esp. Brit., /zen"ith/ , n.
1. the point on the celestial sphere vertically above a given position or observer. Cf. nadir .
2. a highest point or state; culmination.
[ 1350-1400; ME cenith zenit, scribal error for zemt samt road, incorrectly read as senit by medieval scribes (cf. Ar samt ar-ras road above (over) one's head, the opposite of nadir ) ]
Syn. 2. apex, summit.
Ant. 1, 2. nadir.