We propose a novel application of clustering analysis to identify regularities in the usage of entities in axioms within an ontology. We argue that such regularities will be able to help to identify parts of the schemas and guidelines upon which ontologies are often built, especially in the absence of explicit documentation. Such analysis can also isolate irregular entities, thus highlighting possible deviations from the initial design. The clusters we obtain can be fully described in terms of generalised axioms that oer a synthetic representation of the detected regularity. In this paper we discuss the results of the application of our analysis to different ontologies and we discuss the potential advantages of incorporating it into future authoring tools