Does the questioner want to ask "What does trademark category 18 mean?" Class 18 of the trademark registration classification. The registrant of a trademark has exclusive rights. Trademark Class 18 means the 18th class of trademark registration classification. Trademark is a specialized legal term. After the brand or part of the brand is registered by the relevant government departments in accordance with the law, it is called a "trademark" , trademarks are protected by law.