A market shift that encourages buyers to increase the amount they wish to purchase at any given price is called a shift. (Insert a single word.)

The single word that fits in the blank is "demand."

In economics, a shift in demand occurs when buyers are willing to purchase more of a good or service at any given price. This can happen due to various factors, such as an increase in consumer income, a change in consumer preferences, or a decrease in the price of complementary goods. When demand increases, the demand curve shifts to the right, indicating that at every price level, a greater quantity is demanded. This shift can lead to higher equilibrium prices and quantities in the market if supply remains constant. Understanding shifts in demand is crucial for businesses and policymakers as it affects market behavior and economic indicators.