Shia

The Shi'a is the name for those who followed Ali when Talha and al-Zubayr opposed him and insisted on seeking vengeance for the blood of Uthman, and Ali set out to fight them until they returned to God's command. So Ibn al-Nadim relates, and he is the only source cited here. ²

Ali used to say "my Shi'a". They were also called the chosen ones, the friends, the "shurta al-khamis" (the guards of the Thursday), and the companions. ²

Ibn al-Nadim explains "shurta al-khamis" by Ali's words to them that he made a bargain with them for Paradise, not for gold or silver. ²

Ibn al-Nadim says that the first to speak on the doctrine of the imamate was Ali ibn Isma'il ibn Maytham al-Tammar. He mentions Hisham ibn al-Hakam, and says that he opened up discussion of the imamate and refined the doctrine. ²

Not covered here: the Shi'a's own view of how their name arose, and the academic view. A second source is needed.