Background:Scenario-based research is widely used across multiple disciplines to study decision-making, coordination, and complex systems. However, inconsistent terminology and insufficient descriptions of scenarios in reports reduce interpretability, hinder replication, and negatively affect inter-organizational collaboration and policymaking. Objective:The aim of this study was to develop a glossary that improves how scenarios are described in scientific and organizational reports. The target group consisted of professional scenarists, researchers, and practitioners from multiple domains, including healthcare, emergency services, security, and simulation-based training, who design, analyze, or use scenarios in their work. Results:Through interviews with nine participants from diverse professional fields, the study identified 46 terms organized into nine categories, including scenario types, components, roles, evaluation, and logistics. The resulting glossary captures both qualitative and quantitative dimensions of scenario design and reporting and reflects a broad shared understanding across organizations, while also highlighting variations in terminology use. Conclusion:The developed glossary provides a structured framework for improving the clarity and completeness of scenario descriptions. It has potential applications as a checklist for reporting and as a tool for enhancing communication and shared understanding between organizations. Further validation is needed to ensure its applicability across additional domains.