Hedge

Opening an opposite or correlated position to reduce the risk of an existing one. In retail trading it is often an expensive alternative to a stop.

Institutional hedging is for managing portfolio risk (options, futures). Holding long and short on the same pair at the same time ("locking") freezes the loss but doesn't solve it; spread and swap costs keep piling up.

Some prop firms ban hedging. Think in net risk: two opposite positions amount to no position, plus costs.