Revocation - Adjudicative decision for permanently withdrawing an individual's clearances based on a personnel security investigation, other relevant information, or both, that a cleared person is no longer eligible for access to classified information.
NIST SP 800-116
Revocation - The process by which an issuing authority renders an issued credential useless. For example, a Certification Authority may revoke certificates it issues. Typically, a certificate is revoked if its corresponding private key is known to be, or suspected to be, compromised, or if the certificate's subject affiliation is changed.