Lord of the rings series. Could I create a business with the name Mordor Entertainement? Or part of a name that is tradmarked? Thorin Oakenshield is trademarked, could I use Oakenshield Entertainment?
One can commit trademark infringement if there is use of a mark where: (a) the mark is the same as -- or similar to -- another mark; and (b) that use will cause likelihood of confusion to a potential consumer, that both marks are indicating a common source of the goods/services.
This answer includes generalizations and there are many caveats. This answer does not form an attorney client relationship. Consider hiring a lawyer to review the specific facts to your individual situation.