![cover image](https://wikiwandv2-19431.kxcdn.com/_next/image?url=https://upload.wikimedia.org/wikipedia/commons/thumb/4/47/Zenith-Nadir-Horizon.svg/640px-Zenith-Nadir-Horizon.svg.png&w=640&q=50)
Nadir
Direction pointing directly below a particular location / From Wikipedia, the free encyclopedia
For other uses, see Nadir (disambiguation).
The nadir[lower-alpha 1][lower-alpha 2] is the direction pointing directly below a particular location; that is, it is one of two vertical directions at a specified location, orthogonal to a horizontal flat surface.
![Thumb image](http://upload.wikimedia.org/wikipedia/commons/thumb/4/47/Zenith-Nadir-Horizon.svg/320px-Zenith-Nadir-Horizon.svg.png)
The direction opposite of the nadir is the zenith.