Reseller

n. distributor, provider, supplier

A reseller is a company or individual that purchases goods or services with the intention of onselling them rather than consuming or using them. This is usually done for profit (but could be onsold at a loss). One example can be found in telecommunications, where companies buy excess amounts of transmission capacity or call time from other carriers and resell it to smaller carriers.
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a middleman; one who buys merchandise to resell it at a profit.