The word “migrant” lies at the heart of contemporary debates surrounding population movements and transborder identities. But what does it really mean, particularly for peoples who share a strong history, culture, and familial ties, such as Mauritanians and Senegalese? While the United Nations’ definition frames this term universally, its perception can vary according to local and historical realities. In this programme, Dialogue Migration brought together the perspectives of a sociologist and a journalist to better understand the implications and limitations of this definition in a context where borders, inherited from colonisation, do not always reflect the social and cultural dynamics of the populations concerned.