A contest that narrows a field of contestants (finalists) to ranked positions, usually in numbered places (1st place/prize, 2nd place/prize, etc.) or a winner and numbered runners-up (1st runner-up, etc.).
A competition that narrows a field of contestants (semifinalists) to a set of finalists, for a subsequent final.
A playoff in the round with only four players or teams left, the stage before the final.