The act of reforming, or the state of being reformed; change from worse to better; correction or amendment of life, manners, or of anything vicious or corrupt; as, the reformation of manners; reformation of the age; reformation of abuses.
Specifically (Eccl. Hist.), the important religious movement commenced by Luther early in the sixteenth century, which resulted in the formation of the various Protestant churches.
The Reformation did not directly touch the question of the true character of God's church. John Nelson Darby
The story of Christian reformation, revival, and renaissance underscores that the darkest hour is often just before the dawn, so we should always be people of hope and prayer, not gloom and defeatism. God the Holy Spirit can turn the situation around in five minutes. Os Guinness
Would the Protestant Reformation have happened without the printing press? Would the American Revolution have happened without pamphlets? Probably not. But neither printing presses nor pamphlets were the heroes of reform and revolution. Rebecca MacKinnon
The Protestant Reformation had a lot to do with the printing press, where Martin Luther's theses were reproduced about 250,000 times, and so you had widespread dissemination of ideas that hadn't circulated in the mainstream before. Nate Silver