I am learning rules of counterpoints using this source. One of the rules there states:
The CF must have a unique culmination (climax).
I would like to be sure that I understand climax properly.
Does it only mean that there should be only one highest (or lowest) tone? Or the rule states more than that?

e.g.this https://www.mymusictheory.com/learn-music-theory/reference/579-counterpoint
– Albrecht Hügli May 03 '19 at 13:21