What is the meaning of Reformation?

noun

• Improvement (or an intended improvement) in the existing form or condition of institutions or practices etc.; intended to make a striking change for the better in social or political or religious affairs.
• A religious movement of the 16th century that began as an attempt to reform the Roman Catholic Church and resulted in the creation of Protestant churches.
  • synonyms: Protestant Reformation
• Rescuing from error and returning to a rightful course.
  • usage: "the reclamation of delinquent children"
  • synonyms: reclamation