'apostatize' originates from Greek, specifically the word 'apostasia', where 'apo-' meant 'away' and 'stasis' meant 'a standing or standing firm.'

'apostatize' changed from Medieval/Neo-Latin 'apostatizare' (or Late Latin formation from Greek) and entered English via Late/Modern Latin and Middle English formations to become the modern English word 'apostatize'.

Initially it referred to 'a standing away' or 'defection' (the noun sense of leaving one's position or loyalty), and over time it evolved into the verb sense 'to abandon or renounce (faith, cause, allegiance)'.