The present article studies the interjective category in Arusa Maasai. By using a canonical, typologically driven approach to interjectionality, the authors test all emotive interjections previously collected in fieldwork in the Arusha region for their compliance with non-formal (semantic and pragmatic) and formal (phonological, morphological, and syntactic) properties associated with emotive interjections across languages. The analysis demonstrates that, when treated holistically, the category of interjections may comply with all canonical interjective features - in case of some features, tokens, and/or uses, compliance is indeed total. Nevertheless, in case of other features, tokens, and/or uses, compliance is less evident, sometimes even marginal. Overall, both the events of compliance and violation are significant for emotive interjections in Arusa as they jointly determine the boundaries and variation of the interjective category envisaged in its totality.