[1] : The Collaborative International Dictionary of English v.0.48

gatecrasher \gate"crash`er\ v. t.
   a person who enters into a party or other social event
   without an invitation, or into a theater or other public
   performance without a ticket.
   pjc

[2] : WordNet (r) 2.0

gatecrasher
     n : someone who gets in to a party without an invitation or
         without paying syn: crasher, unwelcome guest
see also:
crasher unwelcome guest 

Gatecrasher >> G Words
Gatecrasher, definition of term: Gatecrasher
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