A eurodollar is simply a US-dollar deposit held at a bank *outside* the jurisdiction of the United States, including foreign branches of US banks. The name is a historical accident: the market began in 1950s London, so the prefix stuck. It has nothing to do with the euro currency. A dollar deposit booked in Singapore or the Cayman Islands is just as much a eurodollar (sometimes an *asiadollar*) as one in London. The defining feature is jurisdiction, not geography or currency: these dollars sit outside the Fed's reserve requirements and outside FDIC deposit insurance.