Longman Dictionary of Contemporary English - currency

~ n 1 the system or type of money that a particular country uses  (The stronger currencies are under pressure in the world markets. | decimal currencies | local currency)  (The local currency is francs.)  (- see also hard currency, single currency) 2 the state of being generally accepted or used  (wide currency (=accepted by many people))  (The idea enjoys wide currency in 20th century fiction. | gain currency (=become accepted))  (Marxism began to gain currency.)