WordNet (r) 3.0 (2006):

Ag
    n 1: a soft white precious univalent metallic element having the
         highest electrical and thermal conductivity of any metal;
         occurs in argentite and in free form; used in coins and
         jewelry and tableware and photography [syn: silver, Ag,
         atomic number 47]

The Free On-line Dictionary of Computing (30 December 2018):

ag

    The country code for Antigua and Barbuda.

   (1999-01-27)