verb (v)

• hold back within(verb.stative)

  Example:
  This soil retains water.
  I retain this drug for a long time.
  The dam retains the water.
  

  source: wordnet30
• allow to remain in a place or position or maintain a property or feature(verb.social)

  Example:
  She retains a lawyer.
  She retained her composure.
  This garment retains its shape even after many washings.
  

  Synonym:
  continue, keep, keep on
  

  source: wordnet30
• secure and keep for possible future use or application(verb.possession)

  Example:
  The landlord retained the security deposit.
  

  Synonym:
  hold, hold back, keep back
  

  source: wordnet30
• keep in one's mind(verb.cognition)

  Example:
  I cannot retain so much information.
  

  source: wordnet30
• To continue to hold; to keep in possession; not to lose, part with, or dismiss; to retrain from departure, escape, or the like.(verb)

  source: webster1913
• To belong; to pertain.(verb)

  source: webster1913