Defining central concepts with accuracy is crucial to any scientific discipline. A recent debate over risk definitions in this journal illustrates the far reaching consequences of divergent definitions. Aven and Renn define risk as a social construct while Rosa defines risk as an ontological fact. Both claim that their definition reflects the common usage of the word risk. Through a semantic analysis this paper points to a constitutive element of what is termed probabilistic agency in the risk concept. In this respect, risk is distinct from danger, and because Rosa’s main argument is based on the apparent synonymy between risk and danger, the premises for his risk ontology are not valid. The paper furthermore argues that Aven and Renn’s attempt to bridge between epistemology and ontology is based on a distinction between a conceptual level of risk and its practical application which is impossible to uphold if a risk definition is to be in accordance with the ordinary usage of the word. The paper concludes by arguing that risks are only real within a subjective ontology.