Definition of GGBN Terms
From GGBN Wiki
Occurrence
An existence of a dwc:Organism at a particular place at a particular time. (Definition from https://dwc.tdwg.org/terms/#occurrence)
Material entity
An entity that can be identified, exists for some period of time, and consists in whole or in part of physical matter while it exists. (Definition from https://dwc.tdwg.org/terms/#materialentity)