a serious accident which happened in 1989 during a football game at Hillsborough, in the city of Sheffield in northern England. 96 people died and several hundred were injured by being crushed when a large crowd of people moved into a small area and could not escape. This event led to changes in the design of football grounds and in the methods used for controlling large crowds safely.
Definition from the Longman Dictionary of Contemporary English Advanced Learner's Dictionary.