demand curve

Definition

Graph curve that normally slopes downward towards the right of the chart (except for a Giffen good, where it slopes toward the left), showing quantity of a product (good or service) demanded at different price levels. Customarily, the price is plotted on vertical ('Y') axis and quantity on the horizontal ('X') axis, and it is assumed that (in the short run) income levels, price of substitutes, and customer preferences, remain unchanged. Demand curves of the individual products are aggregated to give a market demand curve and, when drawn together with the supply curves, show the equilibrium price at the intersection of the two curves.