extension mechanism for elements A single definition of a competence, educational objective etc A string in a human language A title for the definition Catenated form of the identifier of a RDCEO A description for the definition A structured form of the definition The model identification for the structured definition A component part of a structured definition Used for statements with free-form text Source identification for a vocabulary token A vocabulary token A container for metadata Used for statements with token values (vocabulary use) The identity of the RDCEO schema - assumed to be IMS RDCEO if absent. The version of the RDCEO schema - assumed to be 1.0 if absent