1. 
   Auto-antonym
   An auto-antonym (sometimes spelled autantonym), or contranym (originally spelled contronym), is a word with a homograph (a word of the same spelling) that is also an antonym (a word with the opposite meaning). Variant names include antagonym, Janus word (after the Roman god), enantiodrome, self-ant...
   Found op http://en.wikipedia.org/wiki/Auto-antonym
   
   
2. 
   autoantonym
   autoantonym A word which can take two, or more, opposite meanings; for example, overlook means 'to watch over carefully' or 'to fail to notice'.
   Found op http://www.wordinfo.info/words/index/info/view_unit/2565/3
   
   

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