CORNER. In commerce, the manipulation of a market to secure the monopoly of the supply of a commodity, or such a degree of control of supply as will enable the speculator to raise prices. From time to time corners have been made in the shares of companies, in corn and in metals. It sometimes happens that when "bears" (see BEAR) sell heavily on the stock exchange the shares of a company which they do not possess, the shares are cornered against them so that they are eventually forced to pay an exor bitant price to buy back what they have sold. There have been large-scale instances of wheat cornering, but such examples are rare, for the risks involved are very great (see MONOPOLY) .