(Britain, colloquial, historical) A quarter of a pound or one crown, historically minted as a coin of approximately the same size and composition as a then-contemporary dollar coin of the United States, and worth slightly more.
(attributive, historical) Imported from the United States, and paid for in U.S. dollars. (Note: distinguish "dollar wheat", North American farmers' slogan, meaning a market price of one dollar per bushel.)
“I have heard it observed that any American settler, even without a dollar in his pocket, would have had something growing by this time.”
“A more telling index of the progress of the War on Terror is the exchange rate between the dollar and the Pakistani rupee.”
“Moreover, Ferry said, the rupiah was benefiting from a weaker dollar vis-a-vis regional currencies.”
dollarization
(economics) The process of a country, officially, or its residents, unofficially, adopting the US dollar or other foreign currency in parallel to or instead of the domestic currency.