This study probed the conceptualization of (in)authenticity in teaching and the way it could be enacted in pedagogical practices. The participants were a purposive sample of 20 Iranian university teachers. Data were collected using in-depth interviews, field notes, and observation. The collected data were analyzed through the lens of hermeneutic phenomenology. The results revealed that authenticity in teaching consisted of themes of being one's own self, pedagogical relationships, contestation, and ultimate meaning which were enacted in the participants' practices through their sense of responsibility, awareness of their possibilities, understanding of pedagogical relationships, self-reflection, critical reflection, and critical hope. Inauthenticity was also conceptualized as teacher-centered classroom manifested in the monologic discourse and traditional assessment which could confirm the dialogical nature of authenticity in teaching. For the participants of the present study, authenticity involved the constant process of becoming that deepened their understanding of themselves and others. Further findings are discussed in the paper.