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

punch line \punch" line`\, n.
   1. the final sentence, phrase, or word in a joke or humorous
      story that is unexpected and produces the humorous effect;
      the point of a joke. wordnet sense 1

   syn: laugh line, gag line, tag line.
        pjc

   2. hence: the final sentence, phrase, or word in any
      narration, speech, or advertisement that produces the
      speaker's intended effect.
      pjc

[2] : WordNet (r) 2.0

punch line
     n : the point of a joke or humorous story syn: laugh line, gag
         line, tag line
see also:
laugh line gag line tag line 

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Bar Line, definition of term: Bar Line
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Air Line, definition of term: Air Line
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Agate Line, definition of term: Agate Line
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