'bahaist' originates from Persian/Arabic, specifically the word 'Bahá' (from Arabic/Persian 'bahā'), where the root meant 'glory' or 'splendor'.

'bahaist' changed from the term 'Bahá'í' (Persian adjective formed by adding the suffix '-í' to 'Bahá'), and was anglicized into English as 'bahaist' (also rendered as 'Baha'i' or 'Bahá'í').

Initially, the element 'Bahá' referred to the name/attribute meaning 'glory' (as in 'Bahá'u'lláh'); over time the derived term referred to members or things relating to the Bahá'í Faith and now means 'a follower of the Bahá'í Faith'.