dollar

Monetary unit of several countries, containing 100 cents. In the USA, the dollar was adopted in 1785. US dollars originally were issued as gold or silver coins; today both metal and paper dollars circulate, but paper predominates. Australia, Canada, and Hong Kong are among the other countries that use the dollar unit, but none of these dollars is equivalent in value to the US dollar.

The US dollar emerged from World War II as the standard currency for international trade. Commodities, even if priced in other currencies, were valued at the prevailing dollar exchange rate. Rising US imports, especially of oil, and government spending resulted in large numbers of dollars held in foreign hands with the resultant devaluation of the dollar by the 1980s. The German mark and the Japanese yen are increasingly important as trading currencies.

See also Eurodollar; petrodollars.