Rate of exchange

relational value of different coins in the world

In finance, the exchange rate (also known as the foreign-exchange rate, forex rate or FX rate) between two currencies specifies how much one currency is worth in terms of the other. For example an exchange rate of 123 Japanese yen (JPY, ¥) to the United States dollar (USD, $) means that JPY 123 is worth the same as USD 1. The foreign exchange market is one of the largest markets in the world. By some estimates, about 2 trillion USD worth of currency changes hands every day.
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Noun
1. the charge for exchanging currency of one country for currency of another
(synonym) exchange rate
(hypernym) rate, charge per unit

See: exchange rate.