The three main Hebrew vocalisation systems—Tiberian, Palestinian, and Babylonian—are well-known in the history of Semitic languages. This article describes another previously undocumented Hebrew vocalisation system, the ‘Arabo-Tiberian system’, a sub-variant of the Tiberian system that appears only in Judaeo-Arabic manuscripts around the tenth and eleventh centuries. In addition to the typical Tiberian vowel marks, the