'pedobaptist' originates from Greek, specifically the elements 'pais' and 'baptizein', where 'pais' meant 'child' and 'baptizein' meant 'to dip or immerse'.

'pedobaptist' changed from ecclesiastical and learned formations such as Latin/Greek-influenced 'paedobaptista' or early modern English 'paedobaptist' and eventually became the modern English word 'pedobaptist'.

Initially, the components referred literally to 'child' + 'one who dips/immerses'; over time the compound came to mean specifically 'one who supports or practices infant baptism' in theological usage.