What does merchant mean?
A company or individual who sells a service or goods. An ecommerce merchant is someone who sells exclusively over the Internet. A merchant will sell the goods to the customer for a profit, and by law will have a duty of care to the customer due to the knowledge of the products he has for sale.
A merchant can be a wholesaler or a retailer, and the products can be sold from any one source to any other source. A merchant is a non-specific term for anyone who sells anything, the only determining factor being that the product or service for sale is being sold for a profit.