**PLEASE NOTE:** For more details on ***running*** the dictionary, please visit: https://github.com/Isabellevdv/grievancedictionary This paper introduces the Grievance Dictionary, a psycholinguistic dictionary which can be used to automatically understand language use in the context of grievance-fuelled violence threat assessment. We describe the development the dictionary, which was informed by suggestions from experienced threat assessment practitioners. These suggestions and subsequent human and computational word list generation resulted in a dictionary of 20,502 words annotated by 2,318 participants. The dictionary was validated by applying it to texts written by violent and non-violent individuals, showing strong evidence for a difference between populations in several dictionary categories. However, classification tasks using the Grievance Dictionary showed that future improvements are still needed. Finally, we provide instructions and suggestions for the use of the Grievance Dictionary by security professionals and (violence) researchers. NOTE: Please refer to the file directory (on the Wiki) or the README file for a guide to the files in this project.