However others suggest Ibadism only took on characteristics of a sect and a full-fledged madhab during the demise of the Rustamid Imamate. The term Wahbi is chiefly derived as an eponymous intimation to the teachings of Abdullah bin Wahb al-Rasibi. Although the term Wahbi was initially considered superfluous as Ibadism was largely homogenous, its usage increased upon the advent of the Nukkari secession in order to differentiate the Wahbis from the off-shoot Ibadis. The most common epithet Wahbi Ibadi clerics enjoined their adherents to apply to themselves is the term "ahl al istiqama" meaning "those on the straight path". They rejected the usage of "ahl al -sunnah" as early usage assigned the term "sunnah" as the practise of Muawiyah cursing Ali ibn Abi Talib from the pulpits, although during the Ummayad era, this meaning changed. Ibadis make up a majority (roughly 75%) of the population in Oman. There are roughly 2.72 million Ibadis worldwide, of which 250,000 live outside Oman. As a result, Oman is the only country in the Muslim world with an Ibadi-majority population. Historically, the early medieval Rustamid dynasty in Algeria was Ibadi, and refugees from its capital, Tiaret, founded the North African Ibadi communities, which still exist in M'zab. The Mozabites, a Berber ethnic group in M'zab, are Ibadis. Ibadism also exists elsewhere in Africa, particularly in Zanzibar in Tanzania, the Nafusa Mountains in Libya, Djerba Island in Tunisia, and among the Dishiishe clan of Somalis. The mainstream branch of Ibadism is Wahbi, although others include notable modern ones include Nukkar and Azzabas.