An Alley-Oop in basketball is an offensive technique or play where one player passes the ball while near the basket to a teammate who then proceeds to jump, catching the ball in midair and dunks or shooting the ball into the basket before dropping it back to the ground.
The term is derived from the French expression ‘Allez Hop!’, which is traditionally said by circus acrobats before they are about to leap.
Alley-Oop was first used in basketball in the 1950s. The term was also used in the National Football League at this time.
Top 10 Alley-Oop Dunks in the 2018 National Basketball Association Season - [Alley-Oop][1]
[1]: https://www.youtube.com/watch?v=kyho17-BgSE