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Legacy system

nounverified·updated May 9, 2026

Outdated computer systems

MWEISACA Cybersecurity Glossary

Senses

Federal Financial Institutions Examination Council (FFIEC) IT Examination Handbook Infobase, Glossary

A term commonly used to refer to existing computers systems and applications with which new systems or applications must exchange information.

NIST SP 800-171r3attested usage pack match

No definition is given in NIST SP 800-171r3. The term is attested in use at 1 citation in that document; a definition is pending curation.

Classifications

Entity Type

System92%llm-generatedllm:claude-haiku-4-5
?unassignedlast reviewed

Sensitivity

unclassified

Information Class

unclassified

Variants

alternatephrasing
Legacy systems
plural
Legacy systemsLegacy systemses
possessive
Legacy system'sLegacy systems's
pluralpossessive
Legacy systems'Legacy systemses'