The Collaborative International Dictionary of English v.0.48:

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]
   [1913 Webster]

   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.

The Collaborative International Dictionary of English v.0.48:

Dawk \Dawk\ (d[add]k), n.
   See Dak.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Dawk \Dawk\, v. t. [Prov. E. dauk to cut or pierce with a jerk;
   cf. OE. dalk a dimple. Cf. Ir. tolch, tollachd, tolladh, a
   hole, crevice, toll to bore, pierce, W. tyllu.]
   To cut or mark with an incision; to gash. --Moxon.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Dawk \Dawk\, n.
   A hollow, crack, or cut, in timber. --Moxon.
   [1913 Webster]