Source : Free On-Line Dictionary of Computing

jaggies
     
         /jag'eez/ (Or "staircase") The "staircase" effect
        observable when an edge (especially a linear edge of very
        shallow or steep slope) is rendered on a {bitmap display} (as
        opposed to a {vector display}).  The effect is even more
        pronounced when a bitmap image or text in a bitmap font is
        enlarged.  {Outline fonts} and {anti-aliasing} are two
        techniques used to solve this problem with text.
     
        [{Jargon File}]
     
        (1997-12-01)