Khilat medieval practice of honouring people with a ceremonial robe. Khilat is an Arabic word meaning dress, particularly of the people of high rank. The Mughals made it an aristocratic institution by way of recognizing ceremoniously loyal and highly active subjects with robes of honour. The practice of khilat seems to have been influenced by the sufi orders. The Shah or leading sufi of the khanqah used to give khilat to senior and spiritually competent disciples capable of initiating lay people to the sufi order.
The practice of khilat was not confined to the royalties alone. It percolated even down to local zamindars and taluqdars. Khilat was extensively practiced by the nawabs. It was against aristocracy for some one to become disloyal to the superior from whom he received khilat. It was, therefore, an effective socio-political weapon to keep people submissive and loyal to the authorities. [Sirajul Islam]