The charm was used to slow an object's momentum or speed. The charm could be used on objects and people and Dumbledore was quick to use the charm on Harry Potter as he fell from his broomstick in a third-year Quidditch match.
Harry Potter and the Prisoner of Azkaban (Book)
Harry Potter and the Prisoner of Azkaban (Film)
Arresto Momentum
Charm
To slow and stop something with momentum