In soccer, the term for a player being sent off for a serious foul is a red card. A player receives a red card from the referee when they commit a serious foul, which typically includes using excessive force, violent conduct, or engaging in malicious actions toward another player. Receiving a red card results in immediate expulsion from the match, and the team must continue with one fewer player. This disciplinary action aims to maintain the integrity of the game and protect the safety of all participants from reckless behavior.