[Perhaps alteration (influenced by pool) of obsolete cesperalle, drainpipe, from Middle English suspiral, vent, from Old French sospirail, breathing hole, from souspirer, to breathe, from Latin suspÄ«rÄre, to sigh; see suspire.]
The Russian Ruble is also known as the Russian Rouble. The United States Dollar is also known as the American Dollar, and the US Dollar. The symbol for RUB can be written R. The symbol for USD can be written $. The Russian Ruble is divided into 100 kopecks. The United States Dollar is divided into 100 cents.
The ruble was the currency of the Russian Empire and of the Soviet Union (as Soviet ruble). Today apart from Russia, Belarus and Transnistria uses currencies with the same name. The ruble was the world's first decimal currency: it was decimalised in 1704 when the ruble became legally equal to 100 kopeks.