What is the negative peak point called on a graph as below?
You're looking for "nadir"
- nadir - (noun) - the worst or lowest point of something.
Examples abound :
- "By 1600 Apalachee had experienced a 17 percent reduction in population size and reached a nadir of 73 percent by the first decade of the 18th century.
- "Public support for the LDP reached a nadir in the 1970s.
- "Thus population growth was quite slow in the 19th century, and the nadir was reached in the first half of the 20th century when France"
- " With the rise of Napolean, Spanish fortunes reached their nadir.
Mathematically speaking, it is called a global/absolute minimum. The smallest value in a set of minima.
There are lots of commonly used words/phrases:
- low point
In my experience, one typically speaks of "peaks" and "valleys".
The other terms mentioned in other answers are not incorrect, but they also are not parallel to the figurative geographic description of the high points as "peaks". Only "valleys" has this appeal.
It can also be called a (negative) peak in some contexts, such as spectroscopy, chromatography (which accounts for most of the hits for "negative peak" on google) and electronics (in peak-to-peak signal amplitudes, one of the peaks is positive, the other negative).