Source : Webster's Revised Unabridged Dictionary (1913)

Chuckle \Chuc"kle\, v. t. [imp. & p. p. {Chuckled}; p. pr. & vb.
   n. {Chuckling}.] [From lst {Chuck}.]
   1. To call, as a hen her chickens; to cluck. [Obs.] --Dryden.

   2. To fondle; to cocker. [Obs.] --Dryden.

Chuckle \Chuc"kle\, n.
   A short, suppressed laugh; the expression of satisfaction,
   exultation, or derision.

Chuckle \Chuc"kle\, v. i. [From lst {Chuck}.]
   To laugh in a suppressed or broken manner, as expressing
   inward satisfaction, exultation, or derision.

Source : WordNet®

chuckle
     n : a soft partly suppressed laugh [syn: {chortle}]
     v : laugh quietly or with restraint [syn: {chortle}, {laugh
         softly}]