This chapter explores the meanings attached to the term 'existential' in hospital chaplaincy in Sweden. In this setting, the term 'existential' has become increasingly popular among chaplains, hospital staff and management, as well as policymakers. Therefore, understanding the connotations of the term is arguably part of the literacy of hospital chaplains who wish to communicate effectively with their environment. The analysis offered in this chapter focuses on the sociological understanding of 'existential' observed in previous research on religiosity in Sweden. The sociological perspective is justified because social sciences are often used to evaluate care practices. Two dominant ways of understanding the 'existential' are observed: Inglehart's theory of 'existential security,' which positions the existential as something outside religion, and substantive approaches to the definition of religion, which see the 'existential' as something religious-like that is not necessarily religious. In contrast to these two dominant views, a functional approach based on Milton Y. Yinger's definition of religion is described and discussed. Arguably, the chapter concludes, Yinger's definition can be seen as an approach to understanding the 'existential' as something at the heart of both religion and secular care practices. As such, it adds to dominant understandings that position the existential as something different or less than religion.