Background As citizen science continues to grow in popularity, there remains disagreement about what terms should be used to describe citizen science activities and participants. The question of how to self-identify has important ethical, political, and practical implications to the extent that shared language reflects a common ethos and goals and shapes behavior. Biomedical citizen science in particular has come to be associated with terms that reflect its unique activities, concerns, and priorities. To date, however, there is scant evidence regarding (...) how biomedical citizen scientists prefer to describe themselves, their work, and the values that they attach to these terms.Methods In 2018, we conducted semi-structured interviews with 35 biomedical citizen scientists in connection with a larger study to understand ownership preferences. Interview data were analyzed to identify the terms that interviewees used and avoided to describe themselves and their work, as well as the reasons for their preferences.Results Biomedical citizen scientists self-identified using three main terms: citizen scientist, biohacker, and community scientist. However, there was a lack of consensus among interviewees on the appropriateness of each term, two of which prompted conflicting responses. Self-identification preferences were based on personal judgments about whether specific terms convey respect, are provocative, or are broad and inclusive, as well as the desirability of each of these messages.Conclusions The lack of consensus about self-identification preferences in biomedical citizen science reflects the diversity of experiences and goals of individuals participating in this field, as well as different perceptions of the values signaled by and implications of using each term. Heterogeneity of preferences also may signal the parallel development of multiple communities in biomedical citizen science. (shrink)