Abstract: Cities are contemporary metropolises that concentrate human and social activity; engineered to support and develop the physical environment and the people within it, Smart cities, we are led to believe, are the immediate future, where smartness is perceived as a characterisation of advancements or digitalisation, in government, mobility and sustainability. Therefore it is not surprising that many organisations are marketing their smart solutions and products, often to a ubiquitous extent and so called smart cities are striving to outperform each other. But how are smart cities actually being defined and how is performance being measured in an era where there is increasing access to unprecedented amounts of foreseen data? This paper identifies the plethora of the smart city definitions and categories evidenced from the literature and shows that 'Smart cities' lacks a robust coherent definition, with many contradicting facts within what constitutes a smart vision. Notably, almost every attempt from organisations, the European Union or cities themselves has failed to define 'smart' in objective terms that can be accepted globally. Certainly, they all are negotiating with a range of descriptors and smart ways to improve the city. Even the UK's attempts to develop a clear definition and set of standards for smart cities (i.e. PAS 180 and PAS 182) appears to suffer from fundamental differences in how the semantic content of a 'smart' city is defined. This paper demonstrates the necessity for a single 'Smart Cities' definition that deals with both the physical and digital using shared parameter value(s) that can be adopted and scaled amongst different localities and within a range of urban contexts adjusting according to existing city condition(s) and vision(s) setting the paradigm for further innovative research in this area.