1. 
   by mouth
   adverb (of drugs) through the mouth rather than through injection; `he was administered the drug orally`
   Found op http://wordnetweb.princeton.edu/perl/webwn?s=by%20mouth
   
   
2. 
   by word of mouth
   [adv] - orally
   Found op http://www.webdictionary.co.uk/definition.php?query=by%20word%20of%20mouth
   
   
3. 
   by word of mouth
   adverb orally; `I heard it viva voce`
   Found op http://wordnetweb.princeton.edu/perl/webwn?s=by%20word%20of%20mouth
   
   

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