'sightless' originates from Old English, specifically the word 'sīhtleas,' where 'sīht' meant 'sight' and '-leas' meant 'without.'

'sīhtleas' transformed into the Middle English word 'sightles,' and eventually became the modern English word 'sightless.'

Initially, it meant 'without sight,' and this meaning has largely remained the same in modern usage.