grand duke

American  

noun

1. the sovereign of a territory called a grand duchy, ranking next below a king.

2. a son of a czar or of a czar's son.

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grand duke British  

noun

1. a prince or nobleman who rules a territory, state, or principality

2. a son or a male descendant in the male line of a Russian tsar

3. a medieval Russian prince who ruled over other princes

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Other Word Forms

• grand-ducal
  adjective

Etymology

Origin of grand duke

First recorded in 1685–95

Example Sentences

First recorded in the collection of King Willem II, it was passed down through royal hands to a German grand duke in the early 20th century.

From New York Times • Dec. 12, 2022

Lucrezia was the fifth child of Cosimo de’ Medici, the grand duke of Tuscany, and his wife, Eleanor de’ Toledo.

From Seattle Times • Sep. 30, 2022

That she and Nicholas, then a grand duke, had an affair is little doubted by historians. 

From Washington Post • Sep. 25, 2017

"Cosimo I, the Medici grand duke, used this to spy on people meeting in the hall," said Giani.

From The Guardian • May 11, 2013

He had become the grand duke of Cold Sassy again.

From "Cold Sassy Tree" by Olive Ann Burns