i don't know but you can go to outher web sites to see if they have the answer
The word "nadir" comes from Arabic "nadir," meaning "opposite." It was borrowed into English from Medieval Latin in the 14th century. In astronomy, nadir is the point on the celestial sphere opposite the zenith and directly below the observer.
Nadir
"Nadir" is the point below you - the point opposite to the zenith.
Nadir comes for the arabic nazir, meaning opposite. Nadir is the direction directly below a point. It is in a way the opposite to Zenith. The word is also used in the meaning of the lowest point.
The opposite of apex is antapex.(Nadir is the opposite of one use of apex, to mean zenith.)
The opposite of zenith (high point, apex) would be nadir(lowest point).Other possible antonyms would be minimum or bottom.In astronomical terms, the point in the sky that is directly over your head is the 'zenith'. The point in the sky that is directly between your feet and down through the Earth is the 'nadir'.
The nadir angle is the angle between the vertical direction and the line of sight to a target from a specific point. To calculate it, you can use the formula: Nadir angle = 90° - θ, where θ is the angle of elevation above the horizontal plane. Alternatively, if you have the altitude of the observer and the distance to the target, you can calculate the nadir angle using trigonometric functions, such as the tangent of the angle being the ratio of the opposite side (height) to the adjacent side (distance).
nadar
Nadir was Erik's friend from Persia.
Nadir Nadirov was born in 1932.
Moyshe Nadir was born in 1885.
Moyshe Nadir died in 1943.