Multidimensional Categorization in Terminological Definitions

EcoLexicon (http://ecolexicon.ugr.es) is a terminological knowledge base on the environment that currently holds 3,351 concepts and a total of 17,475 terms in English, Spanish, German, Russian, French, and Modern Greek. Concepts are linked by means of hierarchical and non-hierarchical relations in dynamic networks and in definitions. The environmental domain is interdisciplinary and its concepts can be categorized from different perspectives, thus conceptual representation needs to be multidimensional. Although, unlike other knowledge resources, conceptual representations in EcoLexicon reflect multidimensional categorization, this has also produced an information overload, particularly at upper concept levels. This means that many concepts show overloaded networks partly caused by multiple inheritance, as many of them have several hyperonyms. However, all conceptual dimensions do not occur at the same time but rather are context-dependent. Since the context of a concept is the set of concepts relevant to its intended meaning, we solved the information overload problem by recontextualizing networks in terms of discipline-based domains. The recontextualization of concepts constrains their relations with other concepts, depending on the activation scenario. By no means, does this imply that these are different senses of a polysemic term, but concepts also vary by context regardless of sense variation. Given that terminological definitions are also an integral part of the representation of multidimensionality, we applied the same contextual constraints to definitional propositions. The result is what we call flexible terminological definitions. This paper describes the representation of context-dependent multidimensionality in EcoLexicon and, more specifically, how this phenomenon is managed in terminological definitions.