"Dumbledore ...ran onto the field as you fell, waved his wand, and you sort of slowed down before you hit the ground."
-- Hermione Granger (PA9)
Arresto Momentum is an incantation that slows the speed or stops a falling object or person to keep them from harm.
References from the canon
- Used during the Quidditch World Cup 2014 by the referee in USA v Jamaica to stop Kquewanda Bailey from hitting the ground (Pm).
Old French arester "to stay, stop" + Latin momentum = "movement"
- Possibly the silent spell used by Dumbledore to slow Harry's fall when he was attacked by Dementors while playing Quidditch in Third Year (PA9).
- First use as a spoken incantation in the film for Deathly Hallows Part 2: Hermione uses the incantation Arresto Momentum to save them when they fell from the Gringotts cart.
From the Web
Arresto Momentum on Harry Potter Wiki