1. 
   Bsw
   British Standard Whitworth. A thread form developed by Sir Joseph Whitworth in 1841. The thread form has rounded roots and crests, the thread form is specified in BS 84: 1956. This thread form was superceded by the Unified thread in 1948 and then the metric thread form.
   Found op http://www.boltscience.com/pages/glossary.htm
   
   
2. 
   BSW
   Behaviour Support Worker
   Found op http://www.kirklees-ednet.org.uk/kirklees/glossary.htm
   
   
3. 
   BSW
   Black Sidewalls
   Found op http://www3.sympatico.ca/dhaughey/j1930.htm
   
   
4. 
   BSW
   Abbreviation for Brettspielwelt, a popular German website that offers real time play of many German-style games. See http://www.brettspielwelt.info
   Found op http://boardgamegeek.com/wiki/page/Glossary
   
   

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