With the Internet being a global resource, Web based applications need to break the barriers of language and culture. The core of an intelligent Web based application comprises an ontological description of the domain. A domain ontology needs a medium for expression, which usually consists of terminology borrowed from a natural language. Thus, a knowledge based application becomes susceptible to linguistic and cultural context. The authors present a novel knowledge representation technique that distinguishes between the abstract concepts in a domain and their expressions. It can associate expressions from different languages with the concepts in an ontology network. Non-textual symbols and media property specifications can also be used to express the concepts using this technique. The resulting ontology can thus be used in a multi-lingual and multi-cultural environment. An RDF based language is used as a vehicle for the knowledge representation scheme. © 2001 IEEE.