'rebaptism' originates from the prefix 're-' (meaning 'again') + 'baptism', ultimately from Greek 'baptisma'/'baptizein' via Late Latin 'baptismus'.

'baptisma' (Greek) gave Late Latin 'baptismus', which passed into Old French as 'baptisme' and Middle English as 'baptisme' or 'baptism'; the English formation 'rebaptism' arose by adding the productive English prefix 're-' to 'baptism' to mean 'again'.

Initially related to the Greek root meaning 'to dip' or 'to immerse', the word evolved to denote the Christian rite of baptism; 'rebaptism' developed to denote performing that rite again.