Rigsdaler is a Danish word that refers to a former currency unit of Denmark. It was used from 1625 until 1873 when it was replaced by the Danish krone. The rigsdaler was also commonly used in Norway and Iceland during the same period. There are several synonyms for rigsdaler, including species, daler, rd, and rix-dollar. These terms were used interchangeably with rigsdaler and refer to the same currency unit. The rigsdaler was the principal currency unit used by Denmark during its colonial period, and it was the currency used for international trade and commerce. Today, the rigsdaler is no longer in use, and the Danish krone is the official currency of Denmark.