toleratie

I updated -atie to make the relationship more clear. The derivation of nouns by replacing -eren of a verb with -atie is a productive process. So creating toleratie from tolereren is completely regular. It is comparable with the conflict between English in- and un-, usually or the other dominates for a certain word, but you still find the other variety occasionally. See unvisible for example. :)

Or even unpossible.  :)