pre·emp·tive / prēˈemptiv/ • adj. serving or intended to preempt or forestall something, esp. to prevent attack by disabling the enemy: preemptive action a preemptive strike. ∎ relating to the purchase of goods or shares by one person or party before the opportunity is offered to others: preemptive rights. ∎ Bridge denoting a bid, typically an opening bid, intended to be so high that it prevents or interferes with effective bidding by the opponents.