This paper surveys the most prominent research done by Swedish scholars of religion in the years 2010-2019 on the subject of the definition of religion in order to ascertain the dominant trends in the findings of this area and speculate as to what prospects these findings offer for the development of a more general definition of religion. The dominant trends are categorised as supernaturality, ineffability and unusability, where the first defines religion in terms of conceptions of supernatural beings, the second defines religion in terms of conceptions of something ineffable or indescribable, and the third maintains that the concept of ‘religion’ is unusable on the grounds that it cannot be coherently defined. These trends are then further categorised in terms of a dichotomy of positive/negative definitions of religion, where positive definitions of religion propose that religion can be coherently defined and negative definitions of religion propose that they cannot. The final and speculative part of the paper offers two roads ahead for future research, firstly to investigate the difficulties inherent in the concept of “supernaturality”, and secondly, in the event that the different religious traditions of the world are found to be ultimately incommensurable, to aim at defining the ways in which different religions define each other.