Forbid or autocorrect a certain term in a vocabulary I am looking for a way to prevent a certain term to be created in a vocabulary. I don't know if there exists a contrib module with this functionality yet. Searches on Google did not deliver so far.

In fact, what I am trying to accomplish is this. In my native language we say "Brussel" but the English version is "Brussels". We have 20 editors and the one uses "Brussels" as a tag, another one uses "Brussel", which ends up with 2 seperate taxonomy overview pages. Yes, I could make it a guideline to use only "Brussel" as a tag, but overtime, they probably forget.

So is there a way that I can 'block' the use of "Brussels" as tag or autocorrect it to "Brussel" when they use "Brussels"? 

Thanks for the help already!
The autocorrection scenario is one the use scenarios covered by the Synonyms module. It's a general purpose tool that works with taxonomy term references (tags) as well as other entities. It also has other integrations with projects that help with mitigating complexities with  duplicate taxonomy terms (e.g. Term Merge).