JACOB HA-KATAN (i.e., "Jacob the Small"; 13th century), Hebrew translator, better known as "The Anonymous" or "The Anonymous of the 13th Century." This is due to the fact that until recently the name of this Hebrew translator of many Arabicand Latin medical works was unknown. However, the author of Sefer ha-Yosher (1270), a pupil of R. Nathan of Montpellier, mentions in his book a number of medical works. Among them is the Antidotarium Nicolai which had been translated by his brother Jacob. Furthermore, he describes Jacob as famous for his works. In the preface to the Antidotarium, the translator introduces himself as "Rabbi Jacob ha-Katan." The same introduction appears in the preface to the translation of Averroes' On Diarrhea and there he also records that he – at the suggestion of *Naḥmanides – translated other works of Averroes. It can, therefore, be assumed that Jacob ha-Katan translated other works without explicitly mentioning them by name.
Muntner, in: Tarbiz, 18 (1947), 194–9; Stein-schneider, Uebersetzungen, 1069–70; Benjacob, Oẓar, 220.