No, please do not use any reference to .com or the like in your business name. If we find that you are doing this we will request that you change it immediately or go so far as to close your account for multiple offenses. We spend a lot of marketing money bringing traffic to your listings and it becomes an issue when users go offsite directly to you for the purchase if they can easily find you.
You may not use business names that may be inappropriate in a business setting if you are an individual without a legally registered business name.