.38 caliber .38 caliber /ˌdɒt ˈθɝːtiˈeɪt ˈkælɪbər/

adjective

1. [American] Of or relating to the bore of a gun (or its ammunition) that measures thirty-eight hundredths of an inch in diameter  ( .38 caliber [American] , .38 calibre [Canadian, British] , .38-caliber , .38-calibre )
   of or relating to the bore of a gun (or its ammunition) that measures thirty-eight hundredths of an inch in diameter
    A .38 caliber shell
   a .38 caliber shell