Seizing the opportunity to take preemptive retaliation for something you know will happen.
Messing around with friends often escalates with some crescendo event that signals the end to the fun. To pretaliate is to abruptly advance the inevitable ensuring that you are never the target. Pretaliatory action must ensure that nobody wants to continue playing.
As Ken and Jim where trading stink bombs while watching the game, Larry quietly decided he would pretaliate by taking a dump in the nacho dip.
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