The Constitution addresses religious minorities in several articles. A close examination of the terminology employed reveals that the manner in which human rights of the nation are affirmed for these minorities, in light of the ummah concept, warrants critical reflection. The present research examines the ambiguities arising from the use of the term "ummah" in the Constitution. Due to its background in religious interpretations, this term has contributed to inconsistency in the substantive and structural elements of the Constitution, raising the question: What impact does the religious concept of ummah have on the human rights of religious minorities? Furthermore, given the legal validity of the Constitution, is it possible to derive a legal conception of ummah that enhances the protection of minorities' rights? In the authors' view, the term ummah, owing to its broad semantic connotations, has led to definitional inconsistency and requires redefinition within a legal framework. Focusing on religious-historical documents, the Constitution of Medina serves as the optimal model for this conceptual revision. From a practical standpoint, this redefinition paves the way for equal rights for all Iranians, regardless of their religion. Using a descriptive-analytical method and library-based sources, this study proposes a unified definition of ummah that guaranteeing their equality and human dignity.