How to better communicate change of name to existing users?

Our product has in the recent years grown and I think that to a new user, a different taxonomy would make more sense. The good thing is that we don't quite have too many existing users yet so I think this would be the best moment to do it. However, for the existing users, I'm not sure what's the best way to inform them that only a few names have changed inside the product, while everything else is still the same?