ETYM French, Spanish, and Italian nadir; all from Arabic nasîru's samt nadir, prop., the point opposite the zenith (as samt), in which nasîr means alike, corresponding to. Related to Azimuth, Zenith.
1. An extreme state of adversity; the lowest point of anything; SYN. low-water mark.
2. The point below the observer that is directly opposite the zenith on the imaginary sphere against which celestial bodies appear to be projected.
Point opposite zenith; lowest point.
The point on the celestial sphere vertically below the observer and hence diametrically opposite the zenith. The term is used metaphorically to mean the low point of a person’s fortunes.

(Khan) (c. 1880-1933) King of Afghanistan from 1929. Nadir played a key role in the 1919 Afghan War, but was subsequently forced into exile in France. He returned to Kabul in 1929 to seize the throne and embarked on an ambitious modernization program. This alienated the Muslim clergy and in 1933 he was assassinated by fundamentalists. His successor as king was his son Zahir Shah.

(1940-) Turkish Cypriot entrepreneur whose business interests in the UK and Cyprus made him one of Britain's 50 wealthiest people. He was declared bankrupt 1990 with estimated debts of Ł100 million. He was charged with theft and false accounting but jumped bail 1993 and returned to Cyprus. He was a major supporter of the Conservative Party, to which he donated over Ł400,000 in the 1990s.