Br

from WordNet (r) 3.0 (2006)

Br
    n 1: a nonmetallic heavy volatile corrosive dark brown liquid
         element belonging to the halogens; found in sea water [syn:
         {bromine}, {Br}, {atomic number 35}]
    2: a Marxist-Leninist terrorist organization that arose out of a
       student protest movement in the late 1960s; wants to separate
       Italy from NATO and advocates violence in the service of
       class warfare and revolution; mostly inactive since 1989
       [syn: {Red Brigades}, {Brigate Rosse}, {BR}]

from The Free On-line Dictionary of Computing (8 July 2008)

br

   <networking> The {country code} for Brazil.

   (1999-01-27)

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

BR
       Boundary Representation (CAD, CAM)