the inherent strength or resistance in a system to withstand external demands without degradation or loss of functionality. Jackson (2016)
 the ability to resist capability degradations under adverse conditions. Brtis (2016)
 The degree to which a system or component can function correctly in the presence of invalid inputs or stressful environmental conditions. (ISO/IEC/IEEE 2010)
 Jackson, Scott. 2016. "Principles for Resilient Design - A Guide for Understanding and Implementation." In IRGC Rresource Guide on Resilience, edited by I. Linkov. University of Lausanne, Switzerland: International Risk Governance Council (IRGC).
 Brtis, John. 2016. How to Think About Resilience in a DoD Context. Colorado Springs, CO: MITRE Corporation.
 ISO/IEC/IEEE. 2010. Systems and Software Engineering - System and Software Engineering Vocabulary (SEVocab). Geneva, Switzerland: International Organization for Standardization (ISO)/International Electrotechnical Commission (IEC)/ Institute of Electrical and Electronics Engineers (IEEE). ISO/IEC/IEEE 24765:2010.
This is a basic attribute of system resilience.