As far as I know, "clicks" is just jargon for the smallest unit of adjustment.
One "click" is 1/4 inch, or 1/4 moa, or 1/8 inch at 100 yards.
Some scopes actually "click", some don't. Most do.
A "click" is the smallest increment, regardless.
If you're 1/2 inch off at 100 and the adjustment is 1/4 inch at 100, then it's 2 "clicks".
Of course, there's also a "klick", which is jargon for a kilometer, but that doesn't have much to do with a scope.