Definition of "grand duchy" []

• A territory ruled by a grand duke or grand duchess. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "(Empress Alexandra of Russia was born in the Rhineland grand duchy of Hesse-Darmstadt.)"
• "While he was spending here the rest of his holidays, he took advantage of an invitation he had received from Prince Radziwill (governor of the grand duchy of Posen, and, through his wife, a daughter of Prince Ferdinand, related to the royal family of Prussia) to visit him at his country-seat Antonin, which was not very far from Strzyzewo."