Legal Question in Business Law in California

The issue is much more trademark than copyright.

It is unlikely there is copyright protection over the name of a character, even for an invented name or word. I am not aware of US authority on that particular issue (though one cannot copyright the name of a real person), but I know that some countries have said that the copyright of a single word is not permissible. Of course, artwork and scripts can be copyrighted, so you must be careful not to infringe upon those.

Your also need to be concerned about trademark law. It is indeed possible to trademark the name of a unique word. You should check the records of the US Patent and Trademark Office to see if this word has been trademarked.

I can all but guarantee you that if you try to use that name you will have some of the most high-powered L.A. entertainment and intellectual property lawyers down on your head in a matter of days. A trademark does not have to be registered to be enforceable and you better believe that the studio or other owners of the rights to that name will be all over you in a heartbeat if you use that name.