1. 
   certain(p)
   [adj] - having or feeling no doubt or uncertainty 2. [adj] - established beyond doubt or question
   Found op http://www.webdictionary.co.uk/definition.php?query=certain(p)
   
   
2. 
   certain(p)
   adjective having or feeling no doubt or uncertainty; confident and assured; `felt certain of success`; `was sure (or certain) she had seen it`; `was very sure in his beliefs`; `sure of her friends`
   Found op http://wordnetweb.princeton.edu/perl/webwn?s=certain(p)
   
   

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