noun (n)

• a copy that corresponds to an original exactly(noun.artifact)

  Synonym:
  duplicate
  

  source: wordnet30
• the act of copying or making a duplicate (or duplicates) of something(noun.act)

  Example:
  This kind of duplication is wasteful.
  

  Synonym:
  gemination
  

  source: wordnet30
• The act of duplicating, or the state of being duplicated; a doubling; a folding over; a fold.(noun)

  source: webster1913