Other forms: wholesalers
A wholesaler is a person or business that sells items to retail stores, which then sell them to individual customers for a higher price.
You could also call a wholesaler a distributor. Anyone who sells goods to other businesses, rather than directly to customers, is a wholesaler. The bookshop in your town and the big-box store in a strip mall are both retailers; they buy goods from wholesalers, who sell them large quantities of books or patio furniture, etc., to be resold to individual shoppers.