In the social sciences, two prevailing definitions of risk are: (1) risk is a situation or event where something of human value (including humans themselves) is at stake and where the outcome is uncertain; (2) risk is an uncertain consequence of an event or an activity with respect to something that humans value. According to these definitions, risk expresses an ontology (a theory of being) independent of our knowledge and perceptions. In this paper, we look closer into these two types of definitions. We conclude that the definitions provide a sound foundation for risk research and risk management, but compared to common terminology, they lead to conceptual difficulties that are incompatible with the everyday use of risk in most applications. By considering risk as a state of the world, we cannot conclude, for example, about the risk being high or low, or compare different options with respect to risk. A rephrasing of the two definitions is suggested: Risk refers to uncertainty about and severity of the consequences (or outcomes) of an activity with respect to something that humans value.