spoiler

Aeronautics. a device used to break up the airflow around an aerodynamic surface, as an aircraft wing, in order to slow the movement through the air or to decrease the lift on the surface and, as a result, provide bank or descent control.

Automotive. a similar device for changing the airflow past a moving vehicle, often having the form of a transverse fin or blade mounted at the front or rear to reduce lift and increase traction at high speeds.

Sports. a team out of final contention that defeats a potential or favored contender and thereby thwarts its chances of winning a championship.

any competitor, entrant, or candidate who has no chance of ultimate victory but does well enough to spoil the chances of another.

information about a plot or event in a movie, book, or show that may spoil the suspense or surprise: Spoilers were leaked before the movie was released. Spoiler alert! Do not read further if you haven't already seen the season finale.

a device fitted to an aircraft wing to increase drag and reduce lift. It is usually extended into the airflow to assist descent and banking: Compare air brake (def. 2)

a similar device fitted to a car

sport a competitor who adopts spoiling tactics, as in boxing

a magazine, newspaper, etc produced specifically to coincide with the production of a rival magazine, newspaper, etc in order to divert public interest and reduce its sales