Other forms: preempted, preempting, preempts
To preempt is to act first so as to prevent somebody else. Preempt the announcement, preempt criticism, a preemptive strike.
The adjective is the heavier word: a preemptive strike is an attack launched to stop one coming, and the legality of that has been argued for a century. In broadcasting, to preempt a programme is to replace it with something else.
1verbpreemptTo act first so as to prevent somebody else.
“The company cut its prices to preempt its rival's big sale.”
preempt is a forestalling.
Also accepted in games: pre-empt
A back-formation from preemption, from Latin prae, before, plus emere, to buy.
Back-formation from preemption. a back-formation from preemption.
Etymology from Wiktionary, CC BY-SA