The Druk Desi (Dzongkha: འབྲུག་སྡེ་སྲིད་; Wylie: 'brug sde-srid; also called "Deb Raja"); was the title of the secular (administrative) rulers of Bhutan under the dual system of government between the seventeenth and nineteenth centuries. Under this system, government authority was divided among secular and religious administrations, both unified under a single leader. Druk, meaning "thunder dragon," refers symbolically to Bhutan, whose most ancient name is Druk-yul. Desi, meaning "regent," was the chief secular office in realms under this system of government.
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