Archdukedom is a term that refers to the dominion of an archduke or archduchess. However, there are other words that can be used interchangeably with the term. Some of these synonyms include duchy, principality, kingdom, and sovereignty. These terms all refer to a region or territory that is ruled by a monarch or a noble title holder. Other related terms include earldom, barony, and lordship. In general, these words are used to describe political entities that hold some degree of authority over a particular region or group of people. The choice of word often depends on the historical context and political structure of the region in question.