A lifecycle state of a key whereby the key is no longer to be used for applying cryptographic protection. Processing already protected information may still be performed.
Sources:
NIST SP 800-152
A key state in which keys are not used to apply cryptographic protection (e.g., encrypt) but, in some cases, are used to process cryptographically protected information (e.g., decrypt).
Sources:
NIST SP 800-57 Part 1 Rev. 5