grand duchy

a territory ruled by a grand duke or grand duchess.

Origin of grand duchy

First recorded in 1825–35

The reason may be that on the continent we have sometimes to ask whether it is empire, kingdom, or grand-duchy that we are in.

Greater Greece and Greater Britain; and George Washington the Great Expander of England |Edward Augustus Freeman
He drove, without stopping, to the grand-duchy, which he reached at two o'clock.

813 |Maurice Leblanc
There is a Belgian province of Luxemburg , until 1839 part of the grand-duchy.

The Nuttall Encyclopaedia |Edited by Rev. James Wood
In order to secure popular support for the Hochberg heir, Charles in 1818 granted to the grand-duchy, under article xiii.

Encyclopaedia Britannica, 11th Edition, Volume 3, Part 1, Slice 2 |Various

Open preparations for revolutionising Lithuania are made in the grand-duchy of Posen.

Blackwood's Edinburgh Magazine, Volume 63, No. 391, May, 1848 |Various

grand duchy

the territory, state, or principality of a grand duke or grand duchess