Although lexical borrowing has always been a central topic in linguistic research, its study has suffered from three major limitations: 1) It has failed to consider social variations in patterns of borrowings. 2) It has assumed a model of two languages in contact. 3) Researchers mostly collect data from communities regardless of the social strata, the political and ideological motivations of the subjects, and conclusions are generalized to the whole community.

This study challenges these assumptions by using a quantitative and qualitative approach to study lexical borrowing in a socially diverse multilingual community, the northern and Southern districts of Saint-Louis, Senegal. In so doing, I explore new methodological and theoretical terrain with broad implications for future research since the vast majority of the world's population today lives in such socially and linguistically diverse communities where language use is often socially, politically or ideologically conditioned.

The primary goal of this research is to demonstrate that in post-colonial francophone multilingual societies such as Saint-Louis, Senegal, loans and the linguistic incorporation processes that accompany them are sociolinguistic variables. This study sheds light on the linguistic nature and the social, cultural, historical, political and ideological importance of lexical borrowing in the multilingual Saint-Louisian speech community in particular and sub-Saharan African communities in general (where multilingualism is the norm).

By means of a quantitative and qualitative methodology, the study demonstrates that there are strong relationships between lexical borrowings and age groups in multilingual communities, and that linguistic processes that go along with lexical borrowings also follow the same pattern. Finally, this study contributes to our understanding of how linguistic, cultural, political and ideological systems around the world articulate with one another through lexical borrowing in both pragmatic and theoretical ways. It also gives us a deeper understanding of the actual linguistic, social, political and ideological nature of lexical borrowings, and provides empirical methodology to future quantitative and qualitative studies of lexical borrowing in the field of linguistics, sociolinguistics and linguistic anthropology. Above all, this study provides a window on the abiding theoretical problem of the study of lexical borrowings as sociolinguistic variables.