Source : WordNet®

Au
     n 1: a soft yellow malleable ductile (trivalent and univalent)
          metallic element; occurs mainly as nuggets in rocks and
          alluvial deposits; does not react with most chemicals
          but is attacked by chlorine and aqua regia [syn: {gold},
           {atomic number 79}]
     2: a unit of length used for distances within the solar system;
        equal to the mean distance between the Earth and the Sun
        (approximately 93 million miles or 150 million kilometers)
        [syn: {Astronomical Unit}]

Source : Free On-Line Dictionary of Computing

au
     
        1.  The two character {country code} for Australia
        used in {Internet} {domain names}.
     
        2.  {audio}.
     
        (1995-02-15)