'Amituofo' originates from Sanskrit, specifically the word 'Amitābha', where 'amita' meant 'infinite' and 'ābha' meant 'light'. The Sanskrit name entered East Asian Buddhism and was rendered in Chinese characters as '阿弥陀佛' (pinyin 'Āmítuófó').

'Amitābha' (Sanskrit) was adopted into Chinese as '阿弥陀佛' (Āmítuófó) and the pronunciation was later transliterated into Latin letters as 'Amituofo' in modern usage among Chinese-speaking Buddhist communities and in English contexts referring to that chant or name.

Initially it referred specifically to the Buddha 'Amitābha' ('infinite light'); over time the Chinese form 'Amituofo' has retained that religious reference but has also taken on secondary uses as a greeting, an exclamation, or a short devotional chant.