Source : Webster's Revised Unabridged Dictionary (1913)

Defaulter \De*fault"er\, n.
   1. One who makes default; one who fails to appear in court
      when court when called.

   2. One who fails to perform a duty; a delinquent;
      particularly, one who fails to account for public money
      intrusted to his care; a peculator; a defalcator.

Source : WordNet®

defaulter
     n 1: someone who fails to make a required appearance in court
     2: someone who fails to meet a financial obligation [syn: {deadbeat}]
     3: a contestant who forfeits a match