What is "dauk"

Dak \Dak\ (d[add]k or d[aum]k), n. [Hind. [dsdot][=a]k.] Post; mail; also, the mail or postal arrangements; -- spelt also dawk, and dauk. [India]

Dak boat, a mail boat.
--Percy Smith.

Dak bungalow, a traveler's rest-house at the end of a dak stage.

To travel by dak, to travel by relays of palanquins or other carriage, as fast as the post along a road.