Escrow
Freezing of funds by a third party (the platform) until the deal's terms are met. In P2P, escrow protects both sides from fraud.
In more detail
Escrow freezes funds with a third party (the platform) until the deal's terms are met, removing the need to trust the counterparty directly. It is the basis of P2P safety: the seller is sure the crypto goes out only after payment, and the buyer that they will receive it. Never transfer outside escrow «by agreement» — that is a classic scam.