Reliable dictionaries are essential for researching linguistic topics related to Hebrew and Arabic. The study of subjects relating to the contemporary use of these languages is facilitated by the accessibility of the necessary lexical tools. But things get more complicated when it comes to dealing with texts written in medieval or early modern forms of Hebrew and Arabic, or different dialects or linguistic varieties. In particular, there is still a serious lack of dictionaries that enable research into Arabic and Hebrew terms which are specific to medieval Judaeo-Arabic (Arabic texts written in Hebrew script). Yet the study of Judaeo-Arabic texts is not only important for exploring Jewish history and literature in the period from the medieval period onwards, but it also constitutes an essential means of gaining an understanding of Middle Eastern history and society and of Muslim and Christian communities. An accurate and correct reading of such critical texts is also essential for precise linguistic analyses, and it is particularly important to identify rare post-classical Arabic terms no longer used in the modern language and thus not found in classical and modern Arabic dictionaries. Following Diem and Radenburg (A Dictionary of the Arabic Material of S.D. Goitein's A Mediterranean Society (Wiesbaden: Harrassowitz, 1994)) and Blau (A Dictionary of Mediaeval Judaeo-Arabic Texts (Jerusalem: Acad. of the Hebrew Language, 2006)), the Judaeo-Arabic dictionary under review written by Modechai Akiva Friedman fulfils this need.