1. 
   believably
   [adv] - in a believable manner
   Found op http://www.webdictionary.co.uk/definition.php?query=believably
   
   
2. 
   believably
   adverb in a believable manner; `he acted believably sincere`
   Found op http://wordnetweb.princeton.edu/perl/webwn?s=believably
   
   
3. 
   believably
   1) Convincingly 2) Credibly 3) In a believable manner 4) Plausibly 5) Probably 6) Realistically
   Found op http://www.mijnwoordenboek.nl/EN/crossword-dictionary/believably/1
   
   

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