Source : Free On-Line Dictionary of Computing

DAU
     
        /dow/ [German Fidonet] D"ummster Anzunehmender User.  A German
        acronym for stupidest imaginable user.  From the
        engineering-slang GAU for Gr"osster Anzunehmender Unfall
        (worst foreseeable accident), especially of a LNG tank farm
        plant or something with similarly disastrous consequences.  In
        popular German, GAU is used only to refer to worst-case
        nuclear accidents such as a core meltdown.
     
        See {cretin}, {loser} and {weasel}.
     
        [{Jargon File}]
     
        (1994-12-06)