Answer: preemption

AnswerCrossword Clue
preemptionThe interruption or replacement of a scheduled radio or television program
preemptionthe act or right of purchasing before others
preemptionThe purchase of goods or shares by one person or party before the opportunity is offered to others
preemptionThe right to purchase public land in this way
preemptionThe action of preempting or forestalling, esp. of making a preemptive attack