You can try a copyright, but, if it works, that word will drop out of usage. Could you imagine the royalties if someone publishes that word in a major magazine?
If you start using the TM mark each time you post or use that word in any public format, it gives you limited protection for further use.
Specifically, if someone else starts using it, and you can show documented history of your use with the TM symbol, they will have to stop using it. If you go further and register the trademark (this is all in the US by the way, don't know how this applies to Europe, if at all), then other companies are required to look on the registered trademark list and see if any logo/catch word/phrase they wish to use is listed. Should they fail to do this, and not know you have registered it, and use it anyway, you have the right to suit.