The lack of a shared, operant definition for greenwashing has led to fragmented scholarly research, unclear guidelines for practice, inconsistent enforcement, and reactive policy frameworks; resulting in ineffective efforts to combat its growth. Using concept analysis, this research establishes a composite definition for greenwashing by identifying the constitutive attributes sourced across 79 scholarly definitions. The analysis finds six requirements necessary for identifying greenwashing: a claim on environmental performance by a private sector organization marketing a product or a service, which cannot be substantiated, made with deceptive intent, and done to establish a competitive advantage. Fulfilling these criteria warrants an accusation of greenwashing. With the aim to prevent its further spread and misuse, the article provides a diagnostic tool for separating similar but often conflated concepts from greenwashing to organize scholarly research, provide guidelines for practitioners, and support regulators’ case analysis.