Source : Webster's Revised Unabridged Dictionary (1913)

Cluck \Cluck\, v. i. [imp. & p. p. {Clucked}; p pr. & vb. n.
   {Clucking}.] [AS. cloccian; cf. D. klokken, G. glucken,
   glucksen, LG. klukken, Dan. klukke; all prob. of imitative
   origin.]
   To make the noise, or utter the call, of a brooding hen.
   --Ray.

Clucking \Cluck"ing\, n.
   The noise or call of a brooding hen.