'nonapostolic' originates from English, specifically formed from the prefix 'non-' meaning 'not' + the adjective 'apostolic', which in turn comes from Late Latin 'apostolicus' and Greek 'apostolikos' (from 'apostolos', 'one who is sent' or 'messenger').

'apostolikos' changed into Late Latin 'apostolicus', then entered English as 'apostolic' in Middle English; the modern compound 'nonapostolic' was formed in English by adding the productive negative prefix 'non-'.

Initially it meant simply 'not apostolic' (i.e., lacking connection with the apostles); over time it has been used specifically to describe churches, doctrines, or claims that do not assert apostolic succession or apostolic authority.