noun (n)

• a discrimination between things as different and distinct(noun.cognition)

  Synonym:
  distinction
  

  source: wordnet30
• the mathematical process of obtaining the derivative of a function(noun.act)

  source: wordnet30
• (biology) the structural adaptation of some body part for a particular function(noun.process)

  Example:
  Cell differentiation in the developing embryo.
  

  Synonym:
  specialisation, specialization
  

  source: wordnet30
• The act of differentiating.(noun)

  source: webster1913