In the context of blockchain and cryptocurrency, "trustless" refers to a system or network in which participants do not have to trust any central authority or individual to accurately and securely facilitate transactions.

In a trustless system, the rules and protocols of the network are enforced through cryptographic mechanisms and consensus algorithms, rather than being reliant on the good faith of any one party. This means that users can transact with each other directly, without the need for a central intermediary to facilitate the transaction or act as a guarantor of its integrity.