'nonreligious' originates from the prefix 'non-' meaning 'not' and the word 'religious' from Latin 'religiosus', where 'religio' meant 'reverence or obligation'.

'religiosus' transformed into the Old French word 'religieux', and eventually became the modern English word 'religious', with 'non-' added to form 'nonreligious'.

Initially, 'religious' meant 'reverence or obligation', but 'nonreligious' evolved to mean 'not relating to religion'.