official language of Pakistan, 1796, formerly also known as Hindustani, from Urdu urdu "camp," from Turkish ordu (source of horde); short for zaban-i-urdu "language of the camp." Compare Dzongkha, a variant of Tibetan and the official language of Bhutan, literally "the language of the fortress." A form of Hindu heavily leavened with Persian and Arabic. "So named because it grew up since the eleventh century in the camps of the Mohammedan conquerors of India as a means of communication between them and the subject population of central Hindustan." [Century Dictionary]

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Definitions of Urdu

Urdu (n.)
the official literary language of Pakistan, closely related to Hindi; widely used in India (mostly by Moslems); written in Arabic script;