How to replace a textual word with a link

[gibilisco69]

Every time a user write a particular word, then I would replace that word with a link.
For example I want to replace google with google [nofollow]

So if someone write a message in this way:
"In my opinion google is the best search engine" then the forum has to automatic replace its message in

"In my opinion google [nofollow] is the best search engine"

Is that possible?

[Kindred]

Although possible, using the censor feature... it is not a great idea.it annoys many users to do that

[gibilisco69]

It works, thank you for your help