1. 
   F2
   This is the product of two F1 plants that have been crossed. This is considered the second generation. This will not necessarily produce a great plant.
   Found op http://www.emilycompost.com/garden_glossary.htm
   
   
2. 
   F2
   The second filial generation. It is in this generation that segregation first occurs.
   Found op http://www.encyclo.co.uk/visitor-contributions.php
   
   
3. 
   F2
   The F2 is a South African 20 mm cannon that fires high speed (1100 m/s) ammunition at a firing rate of 740 rounds per minute.
   Found op http://www.probertencyclopaedia.com/browse/FYF.HTM
   
   

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