the reduced consumption of a good whose price has increased that is due to the reduction in a person's buying power, or "real" income; when a person's real income is lower, normally she will consume less of all goods, including the higher priced goo

The effect that a change in income has on the quantity of a good or service consumed.

When the price of a good rises, other things remaining the same, the price rises relative to people's incomes. Faced with a higher price and an unchanged income, the quantities demanded of at least some goods and services must be decreased. Normally, the good whose price has increased will be one of the goods bought in a smaller quantity.