'baptism' originates from Greek, specifically the word 'baptisma' (from the verb 'baptizein'), where the root 'baptein' meant 'to dip' or 'to immerse'.

'baptism' changed from Late Latin 'baptisma' and Old French 'baptisme' into Middle English 'baptisme' and eventually became the modern English word 'baptism'.

Initially, it meant 'the act of dipping or immersing'; over time it became specialized to mean the Christian sacrament of initiation and later acquired figurative senses such as 'a testing initiation' (e.g., 'baptism of fire').