 The choice of words used to describe citizen science can greatly impact its development, as it influences how knowledge is gathered, social action taken, and information sharing occurs. This article explores various terms and expressions used to refer to citizen science and its practitioners, providing guidance for the future growth of this field by reviewing theoretical, historical, geopolitical, and disciplinary contexts, discussing what citizen science is, and suggesting potential terms and definitions. While no single term is appropriate for all contexts, careful consideration should be given when choosing terminology for a specific citizen science project, and direct communication with participants about how terminology affects them should occur. A more systematic study of terminology trends in citizen science is recommended. This article was authored by M. V. Itzel, Jessica L. Cappadonna, Chris Santos-Lang, and others.