'supercilious' originates from Latin, specifically the word 'superciliosus,' where 'supercilium' meant 'eyebrow' or 'haughty demeanor.'

'superciliosus' transformed into the French word 'supercilieux,' and eventually became the modern English word 'supercilious' through Middle English.

Initially, it meant 'haughty demeanor,' but over time it evolved into its current meaning of 'behaving as though one is superior to others.'