'blasphemy' originates from Greek, specifically the word 'blasphemia', where 'blasphemein' meant 'to speak evil of' or 'to slander.'

'blasphemy' came into English via Latin 'blasphemia' and Old French 'blasphemie' before appearing in Middle English as 'blasphemie' and later becoming the modern English 'blasphemy.'

Initially, it meant 'evil-speaking' or 'slander'; over time it narrowed to mean 'sacrilegious or irreverent speech or actions toward the divine or sacred.'