'stupefy' originates from Latin, specifically the word 'stupefacere', where 'stupe-' came from Latin 'stupēre' meaning 'to be stunned' and 'facere' meant 'to make'.

'stupefy' changed through Medieval Latin 'stupefacĕre' and Old French forms such as 'estupéfier' and entered Middle English (e.g. 'stupefien'), eventually becoming the modern English 'stupefy' and its derived forms like 'stupefied' and 'stupefiedly'.

Initially it meant 'to make numb or insensible', but over time it evolved into its current sense 'to astonish, shock, or render incapable of clear thought'.