declassification
Refers to the act of removing classified status from documents or information, making them publicly accessible.
The government decided to declassify the document.
The declassified information was released.
機密 means 'classified' or 'secret', while 機密解除 is the action of removing that classification.
解除 means 'cancellation' or 'release' in general; 機密解除 specifically applies to classified information.
Compound of 機密 (classified, secret) and 解除 (release, cancellation).