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.