Answer:
spoiler (plural spoilers)
1.A document, review or comment that discloses the ending or some key surprise, or twist in a story.
Good netiquette dictates that one warn of spoilers before discussing them, so that readers who wish to do so may experience the surprises for themselves.
2.(aeronautics) A device to reduce lift
3.(automotive) A device to reduce lift and increase downforce
4.(politics, gaming) An individual unable to win an election or game for him- or herself, but with the power to determine which player or candidate among two or more others does win.
5.(trading card games) A comprehensive list of objects and their characteristics.