Active Cyber Defense Glossary Definition

Active Cyber Defense is a security-operations concept used to detect, monitor, investigate, or respond to activity that may affect an organization's security posture.

Active Cyber Defense appears in monitoring workflows, incident reports, response playbooks, tabletop exercises, and security-operations metrics. It is retained here because professionals may encounter the term in NIST guidance, security reviews, or technical documentation and need a concise public explanation.