SKOS (Simple Knowledge Organization System) Concept An idea or notion; a unit of thought. Public description modified from the information on this page: http://www.w3.org/TR/2005/WD-swbp-skos-core-guide-20050510/#sechierarchy . narrower term related broader term Public description modified from the information on this page: http://www.w3.org/TR/2005/WD-swbp-skos-core-guide-20050510/#sechierarchy .