[1] : The Collaborative International Dictionary of English v.0.48

noun \noun\ noun, n. of. noun, nun, num, non, nom, f. nom,
   fr. l. nomen name. see name. gram.
   a word used as the designation or appellation of a creature
   or thing, existing in fact or in thought; a substantive.
   1913 webster

   note: by some grammarians the term noun is so used as to
         include adjectives, as being descriptive; but in
         general it is limited to substantives.
         1913 webster
see also:
name 

[2] : WordNet (r) 2.0

noun
     n 1: a word that can be used to refer to a person or place or
          thing
     2: a word that can serve as the subject or object of a verb

Noun >> N Words
Noun, definition of term: Noun
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Noun Phrase >> N Words
Noun Phrase, definition of term: Noun Phrase
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Proper Noun >> P Words
Proper Noun, definition of term: Proper Noun
proper+noun_pag1.html

Common Noun >> C Words
Common Noun, definition of term: Common Noun
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