1. 
   jump off
   [v] - set off quickly, usually with success
   Found op http://www.webdictionary.co.uk/definition.php?query=jump%20off
   
   
2. 
   jump off
   verb set off quickly, usually with success; `The freshman set off to a good start in his math class`
   Found op http://wordnetweb.princeton.edu/perl/webwn?s=jump%20off
   
   
3. 
   Jump-Off
   In the event of a tie, a course may be altered and the two tied horses asked to jump again
   Found op http://www.gaitedhorses.net/Articles/HorseGlossary.html
   
   

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