Introduction. Mental health and psychiatry have been terms of intense and complex use for almost a century, and they may have reached a critical level of ambiguous and imprecise synonymy that makes their definition and validation difficult. Objective. To examine these concepts in depth, establishing precise distinctions, ontological connections, and instrumental scope reinforced by well-defined ideas in ethics and bioethics. Method. Narrative review of pertinent literature, consultation with diverse scientific, medical, historical, philosophical, and literary sources, with appropriate analysis of ethical and bioethical practices. Results. A broad, comprehensive definition is elaborated of mental health as a field with sociocultural, political, and demographic implications, and of psychiatry as a medical specialty. In addition to making clear distinctions and describing the specific impact of both fields on diverse populations, various levels of conceptual linkages, sociopolitical action, and ethical content are highlighted, as well as in processes of administration, education, and research. Discussion and conclusion. There are factors that reinforce or weaken the scope of mental health and psychiatry, including their ethical and bioethical dimensions. Their effectiveness requires a reaffirmation of objectives and the reinforcement of individual and institutional initiatives, as well as the search for authentic connections and a social projection that is objective, comprehensive, and just.