Adherents of Shi鈥榠sm, the second largest denomination of Islam, after Sunnism; those who, in addition to following the sunna of Prophet Muhammad, believe in the Imamat of 士Al墨 b. Ab墨 峁乴ib and his descendants through Fatima. The three primary Shi鈥榠 groups are the Ithna鈥榓sharis , the Ismailis and the Zaydis.