A cross rate refers to the exchange rate between two currencies which is derived from their individual exchange rates with a third currency, often the US dollar.
Dollar drain refers to the amount by which a foreign country's imports from the United States exceed its exports to the United States, leading to a depletion of the country's dollar reserves.
A mechanism whereby an exchange rate can be calculated between two currencies for which no direct rate of exchange exists. The US dollar, which is customarily used as the vehicle currency in foreign-exchange trading, functions as the common denominator for such calculations.
