This is a reference to some of the various terms used in early sources to refer to Jaʿfar al-Ṣādiq and his followers, the Jaʿfarīs (e.g., aṣḥāb Jaʿfar), during and after Jaʿfar's lifetime.
This source is part of the Online Companion to Hossein Modarressi, Text and Interpretation: Imam Jaʿfar al-Ṣādiq and His Legacy in Islamic Law (Harvard University Press, 2022).