Noun br has 2 senses
- bromine, Br, atomic number 35 - a nonmetallic largely pentavalent heavy volatile corrosive dark brown liquid element belonging to the halogens; found in sea water
--1 is a kind of chemical element, element; halogen
--1 is a substance of seawater, saltwater, brine
- Red Brigades, Brigate Rosse, BR - a Marxist-Leninist terrorist organizaiton 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
--2 is a kind of terrorist organization, terrorist group, foreign terrorist organization, FTO
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