n.
1.improvement (or an intended improvement) in the existing form or condition of institutions or practices etc.
2.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
3.rescuing from error and returning to a rightful course
Idiom of the Day
blue in the face
to be exhausted and speechless
You can argue with him until you are blue in the face but you will never change his mind.