Dehumanization is the perception of someone less than human. Several studies have used innovative approaches to investigate the subtle ways in which humanity can be denied. While most of these models clearly distinguish humans from animals and robots, none adequately capture the huge range of dehumanization that exists in metaphorical thought, such as disease-related metaphors (i.e., biologization). Building on existing theoretical frameworks concerning dehumanization, we developed a set of items (i.e., the Tripartite Agency Attribution Scale) measuring the capacity to experience emotions (affective mental states), produce effective actions (behavioral potential), and think rationally (cognitive abilities), and demonstrated the relevance of this approach to assess biological dehumanization. Study 1 (N = 512) and Study 2 (N = 237) consistently showed that viruses (vs. animals vs. humans) are perceived as possessing behavioral potential but lacking affective mental states and higher-order cognitions. Accordingly, Study 3 (N = 250) showed that biologized (vs. animalized vs. mechanized vs. non-dehumanized) social groups in Italian society are perceived as primarily possessing behavioral potential with limited affective and cognitive abilities. Our research provides empirical evidence of a new, subtle way to investigate one of the most understudied forms of dehumanization, while also expanding the literature on this process.