Oligopsony

n. strong influence of a small group of buyers (Economics)

An oligopsony is a market form in which the number of buyers is small while the number of sellers in theory could be large. This typically happens in market for inputs where a small number of firms are competing to obtain factors of production. It resembles an Oligopoly, where there are many buyers but just a few sellers. An oligopsony is a form of Imperfect competition. The terms monopoly (one seller), monopsony (one buyer), and bilateral monopoly have a similar relationship.
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A market characterized by a small number of large buyers who control all purchases and therefore the market price of a good or service.