Source : WordNet®

ascender
     n 1: someone who ascends
     2: a lowercase letter that has a part extending above other
        lowercase letters
     3: (printing) the part of tall lowercase letters that extends
        above the other lowercase letters

Source : Free On-Line Dictionary of Computing

ascender
     
         A lowercase letter that extends above the "x-height"
        (the height of the letter "x"), such as "d", "t", or "h".
        Also used to denote the part of the letter extending above the
        x-height.
     
        Compare {descender}.
     
        (1998-03-27)