Hassaniya is the Arabic spoken in Mali, Mauritania, and the Western Sahara. It reflects the speech of the Arabian beduin tribes (Banu Hisan and Ma'qil) who arrived in the Maghreb via Egypt in the 11th century. Hassaniya is completely different from mainstream Maghrebi Arabic, especially that of Morocco and western Algeria, which took shape after the original Arab invasion of the 7 th century. In Mali (unlike Mauritania), Hassaniya is a minority vernacular with little exposure to the literary language. It is as "pure" a beduin Arabic as one can find in the Arab world today. This dictionary, and the volume Hassaniya Arabic (Mali): Poetic and Ethnographic Texts_ in the same series, document Hassaniya as spoken in sahelian and desert areas near Timbuktu and the Medieval imperial city Gao on the Niger River. They are based primarily on recordings and lexicographic study made in the late 1980's. The dictionary functions in part as a glossary for the texts, and lexical entries include many page-line references to textual occurrences. Glosses are given in French as well as English to maximize the dictionary's usefulness to multiple audiences.