Source : WordNet®

demo
     n : a visual presentation showing how something works; "the
         lecture was accompanied by dramatic demonstrations"; "the
         lecturer shot off a pistol as a demonstration of the
         startle response" [syn: {demonstration}]

demo
     v : show or demonstrate something to an interested audience;
         "She shows her dogs frequently"; "We will demo the new
         software in Washington" [syn: {show}, {exhibit}, {present},
          {demonstrate}]

Source : Free On-Line Dictionary of Computing

demo
     
        /de'moh/ 1. A demonstration of a product, often of an early
        version or prototype.  A demo is a far more effective way of
        inducing bugs to manifest themselves than any number of {test}
        runs, especially when important people are watching.
     
        2. {demo version}.
     
        3. A program written to demonstrate the programmer's coding
        ability and/or the power of the computer it runs on.  Such
        demos are nearly always written in {machine code} and
        traditionally feature scrolling text about the author, his
        friends, his code and anything else he fancies and animated
        graphics.
     
        [{Jargon File}]
     
        (1994-11-04)