Commercial bank: A bank that offers a broad range of deposit accounts, including checking, savings, and time deposits, and extends loans to individuals and businesses -- in contrast to investment banking firms such as brokerage firms, which generally are involved in arranging for the sale of corporate or municipal securities.

Common market: A group of nations that have eliminated tariffs and sometimes other barriers that impede trade with each other while maintaining a common external tariff on goods imported from outside the union.

Common stock: A share in the ownership of a corporation.

Consumer price index: A measure of the U.S. cost of living as tabulated by the U.S. Bureau of Labor Statistics based on the actual retail prices of a variety of consumer goods and services at a given time and compared to a base period that is changed from time to time.