We develop the Dislocation Ontology Suite (DISOS) as an essential step towards allowing the establishment of FAIR (Findable, Accessible, Interoperable, and Reusable) data in the MSE domains. DISOS is an ontology suite that comprises four modules describing scientific concepts of materials, representations of dislocations, and different simulation models in the dislocation domain. Furthermore, DISOS is used to describe dislocation-related data to increase interoperability in dislocation use cases.