'impious' originates from Latin, specifically the word 'impius', where 'im-' meant 'not' and 'pius' meant 'dutiful or pious'.

'impius' transformed into the Old French word 'impie', and eventually became the modern English word 'impious' through Middle English.

Initially, it meant 'not dutiful or pious', but over time it evolved into its current meaning of 'lacking reverence or respect, especially towards a deity or religion'.