The term “Urdu” is from Turkish.
During the eighteenth century, Persian was the language of intellectual and artistic life in Muslim South Asia as well as the official language of government and administration. The Persian culture influenced Central Asia, Iran, and even Turkey. The Turko-Persian culture was associated with various ruling dynasties. Its sphere of influence extended to the scholars and learned members of the community. Poets, artists, scholars in cities such as Delhi, Lahore, and Dacca spoke the same language as those in Heart (Afghanistan), Bukhara (Uzbekistan, Central Asia) and Isfahan (Iran). The Turkish-Persian culture continued to remain strong and exert an influence on the languages in a variety of ways. When, for example, the scholars and learned members of the community began to express themselves in an indigenous language, they called it by a Turkish name, “Urdu,” meaning “military camp,” presumably because the language originated as a means of communication between Turkish soldiers and the local population.
Source: Website of The Institute of Ismaili Studies