Semantic Interoperability of digital twins in smart cities is crucial for improving the efficacy and compatibility of digital twins’ communication, which will result in improved smart cities and lifestyles. Without constant interoperability improvement, it will be impossible to effectively communicate and share information between digital twins. This paper examines the possibility of interoperability enhancement focusing Microsoft Azure Digital Twin Definition Language (DTDL) and discusses future research ideas that could contribute to the enhancement of Azure DTDL.