The term 'PREFIX WITH JOHN OR GOD' can be solved by the word 'DEMI', which is a four-letter prefix. It is derived from the Greek word 'demiourgos' meaning 'public worker' or 'ARTISAN'. The prefix is commonly used to refer to a person who is only partially divine, such as John the Baptist or Jesus Christ. It is also used to refer to a person who is only partially human, such as the demigod Hercules.