Longman Dictionary of Contemporary English
single currency
noun
EXAMPLES FROM CORPUS
▪ Countries that meet this criteria by 1998 will qualify for the single currency.
▪ Few, though, believe Britain will join the single currency when it is scheduled to begin in January 1999.
▪ I believe that it is possible to have a perfectly satisfactory single market without a single currency.
▪ If at some stage we entered into a single currency, we should have to deal with a different matter.
▪ It came at a moment when skepticism over the pace toward full economic union and the single currency has been mounting.
▪ One of these is, of course, the single currency.
▪ The engine that is meant to pull the unity Euro-train is a single currency.
▪ The Leader of the Opposition previously expressed three conditions for joining a single currency.
Wiktionary
single currency
n. The unified currency proposed for all EU states; it became the Euro.
Usage examples of "single currency".
When the world went on a single currency, they'd tried to coordinate it with the food rationing in some way, hoping to eventually eliminate the ration books, so they'd made the new currency K'S, kilocalories, because that's the unit for measuring the energy equivalent of food.