Trust Anchor
A Trust Anchor is an authoritative entity, represented by a public key and its associated data, that a relying party accepts as the starting point for verifying a chain of trust, based on the model in RFC 5914.
A verifier does not re-establish trust from scratch every time it checks a credential: it follows a chain of certificates or attestations back to a Trust Anchor it has already decided to trust, and if that chain resolves cleanly, everything below it is trusted by extension. In the EUDI ecosystem, a Trusted List published by a member state acts as a registry of Trust Anchors, telling relying parties which public keys back qualified trust service providers, so they do not need a separate trust relationship with every issuer individually.