grand duchy 
noun
A state or territory ruled by a grand duke or duchess.June 9, 1815, after 400 years of domination by various European nations, Luxembourg was made a grand duchy by the Congress of Vienna....
- Led by William's daughter, the Grand Duchess, the grand duchy cooperated with the Germans in their unlawful violation of Luxembourg's neutrality during World War I.
- Belgium became part of a new kingdom of the Netherlands and then, after 1831, a separate realm in her own right; Luxembourg became an independent grand duchy.
- crown hunter
- crown imperial
- crowning glory
- crowning-in
- crowning jewel
- crownings-in
- crown jewel
- Crown Jewels
- crown knot
- crown labourer
- Crown land
- crown law
- crown lawyer
- crown lens
- crownless
- crownlet
- crown living
- crown lock
- crown moulding
- crown octavo
- Crown Office
- Crown Office and Procurator Fiscal Service
- crown of thorns
- crown paper
- crown piece