The discipline of information science per definition deals with data, information and knowledge, and the interrelationships between these concepts. Lexicography in essence also deals with data, information and knowledge, humans and technology and the interaction between these three components. In the Web and many other environments, a subset of elements was developed to describe information objects, namely the Dublin Core Metadata Initiative (DCMI). The Dublin Core (DC) metadata set contains 15 elements, which is too restricted to describe all information objects in sufficient detail. The Dublin Core set of elements is therefore often combined with other metadata schemas in the Resource Description Framework (RDF). A redefined theory of lexicography needs to reflect these contributions but should also display a comprehensive nature that gives a sound theoretical basis to the lexicographic practice that responds to the needs of diverse and wide-ranging potential target user groups.