A punkah (Hindi and Urdu pronunciation: pankha) is a type of fan used in the early 500 B.C.. In its original sense the punkah was a portable fan made from the leaf of the palmyra.
In the colonial age, the word came to be used in a special sense by Anglo-Indians in British India for a large swinging fan, fixed to the ceiling, and pulled by a coolie, called the punkawallah, during the hot weather.
The date of this invention is not known, but it was familiar to the Arabs as early as the 8th century. The punkah was not commonly used in India before the end of the 18th century.
The electric fan largely supplanted it in barracks and other large buildings at the beginning of the 20th century.
The term was carried over to punkah louvre, to refer to the outlet for (cool) air in aircraft, particularly those over the passenger seats.