Ayatollah (UK: or US: ; Persian: آيتالله, translit. āyatullāh, from Arabic: آية الله, translit. ʾāyatu llāh "Sign of God") or ayatullah is a high-ranking Usuli Twelver Shī‘ah cleric. Those who carry the title are experts in Islamic studies such as jurisprudence, Quran reading, and philosophy and usually teach in Islamic seminaries. The next lower clerical rank is Hujjat al-Islam.