Definition of "duchy" [duch•y]

• The territory ruled by a duke or duchess; a dukedom. (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.

• "Active judicial intervention in the duchy was the Capetians most effective weapon in their struggle with the Plantagenets over ducal authority."
• "The district ceded to Rollo developed into what in later times was known as the duchy of Normandy."
• "Among the numerous lakes which belong to the duchy are the Mummel, Wilder, Eichener and Schluch, but none of them is of any size."