pre-emptive
/ˌpriːˈemptɪv/adjective
1- serving or intended to pre-empt or forestall something, especially to prevent attack by disabling the enemy抢先的, 先发制人的：
pre-emptive action
先发制人的行动
a pre-emptive strike.
先发制人的打击。
1.1
- relating to the purchase of goods or shares by one person or party before the opportunity is offered to others优先购买的：
pre-emptive rights.
优先购买权。
1.2
- Bridge denoting a bid, typically an opening bid, intended to be so high that it prevents or interferes with effective bidding by the opponents【桥牌】（尤指开叫）阻击性开叫的, 先发制人开叫的。