Punishment
A consequence that follows a behaviour and decreases the future frequency of that behaviour.
Punishment is a consequence that reduces the future frequency of a behaviour. Like reinforcement, it can be positive (adding an aversive stimulus) or negative (removing a preferred stimulus).
While punishment quickly suppresses dangerous behaviour, it carries heavy ethical and practical baggage. It never teaches a replacement behaviour and routinely causes emotional side effects or aggression. Modern practice relies heavily on reinforcement-based interventions and uses punishment only as a last resort.