Dzongkha language
Bhutan is also called Druk in Bhutanese language, Dzongkha. This is related to the imaginary figure in skies usually refered as Thunder Dragon and hence Bhutan is sometime called country of Thunder Dragon.
Historically, dragon is accociated to Tibet of China. Whne the famous Tibetan saint Shabdrung Nwawang Namgyal entered Bhutan, forced by the rival kings to leave his kingdom in Kham, he named Bhutan as Druk. As the country was called Druk, its citizens are called Drukpa, when is mostly used even at this time but as the country has been represented by the name 'Kingdom of Bhutan', use of Druk to represent this kingdom has been gradually diminishing.
Today, this word is commonly used to refer the people from northern part of the country who are of Tibeto-origin. Bhutanese refugees accuse that this identification has been created to disintegrate from the mainstream and finally expell them. When tension grew between northern and southern Bhutanese, some influential persons from northern Bhutan widely campaign that Drukpa does not refer the southern Bhutanese, rather they are called Lhotsampas, means residents of the south
Most institutions in the country use Druk in their name such as Druk National Congress, Druknet, Druk Air etc.