In this article we describe a theoretical and practical approach to the analysis of phraseological units, specifically terminological phrasemes (Meyer and Mackintosh 1994, 1996), as entities determined by predicate relations, leaving aside, therefore, the traditional view of collocations and compounds as static structures following specific syntactic patterns. Instead, we claim that these units can be considered as terminographic formalizations of a conceptual structure, a phraseme template, established according to certain ontological patterns. This phraseological analysis accounts for phenomena such as multidimensionality, recursiveness and inheritance, which pose a problem in the management of multiword units. We are currently implementing this methodology in OntoTerm®, a concept-oriented tool for terminology management used in a research project called OncoTerm, whose scope of study has been, so far, the subdomain of oncology.