Real GNP, or real gross national product, refers to the measure of a country's economic output that has been adjusted for inflation. There are several synonyms for the term, including "real GDP," which stands for real gross domestic product, and "constant dollar GNP," which refers to GNP measured in terms of a fixed value of money. Other synonyms include "inflation-adjusted GNP," "constant-price GNP," and "chained-dollar GNP." These terms all refer to the same essential concept, which is the need to adjust a country's economic output for the impact of inflation so that accurate comparisons can be made across time periods or between countries.