This is a potential security issue, you are being redirected to https://csrc.nist.gov.
An entity other than the key pair owner and verifier that is trusted by the owner or the verifier or both. Sometimes shortened to “trusted party.”
FIPS 186-5 under Trusted Third Party
An entity other than the owner and verifier that is trusted by the owner, the verifier or both to provide certain services.
NIST SP 800-89 under Trusted Third Party