The term 'Characteristic Mark' can be solved by the crossword solution 'STAMP' (5 letters). A STAMP is a device used to make an impression in wax, clay, paper, or some other medium. It is often used to indicate a date, or to authenticate a document. Stamps are also used to mark goods as having been inspected or taxed. They are also used to show ownership, or to indicate that a product has been approved for sale.