Source : WordNet®

icebreaker
     n 1: a ship with a reinforced bow to break up ice and keep
          channels open for navigation [syn: {iceboat}]
     2: a beginning that relaxes a tense or formal atmosphere; "he
        told jokes as an icebreaker"

Source : Free On-Line Dictionary of Computing

icebreaker
     
         A program designed for cracking security on
        a system.
     
        See also: {ICE}.
     
        [{Jargon File}]
     
        (2000-03-18)