grand duke grand duchy of luxembourg • grande dame · · · Info · Definitions · Characters · · grand duke · · Text Common · · Latin · · Scripts 10 · · Length 2 · · Syllables Definitions · · · (noun) a prince who rules a territory. Synonyms: grand duke. · · Noun Definition 1 Characters · · space U+0020 a latin small letter a U+0061 d latin small letter d U+0064 e latin small letter e U+0065 g latin small letter g U+0067 k latin small letter k U+006B n latin small letter n U+006E r latin small letter r U+0072 u latin small letter u U+0075