'blasphemer' originates from Greek, specifically the word 'blasphemein,' where 'blapto' meant 'to hurt' and 'pheme' meant 'speech'.

'blasphemer' changed from Old French 'blasphémateur' and Middle English 'blasphemer' and eventually became the modern English word 'blasphemer'.

Initially, it meant 'to speak injuriously or slanderously,' but over time it evolved into its current meaning of 'to speak irreverently about God or sacred things'.