DuckCorp Dico

Found one definition

1.                 From The Jargon File (version 4.4.7, 29 Dec 2003):
                   
   
   
                   
                     
   char
    /keir/, /char/, /kar/, n.
       Shorthand for ‘character’. Esp.: used by C programmers, as char is C's
       typename for character data.