Ever since you first toddled into a school house door, your teachers have been telling you that a noun is a person, place or thing.  
Unfortunately, some erudite linguists have demonstrated that such a definition is entirely too simple.  

But since we aren't linguists, we will lock those fellows in the closet (metaphorically speaking, of course) and hang on to the definition we know: A noun is a person place or thing.
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