'unsightliness' originates from the Old English word 'unsīhtlīc,' where 'un-' meant 'not' and 'sīht' meant 'sight.'

'unsīhtlīc' transformed into the Middle English word 'unsightly,' and eventually became the modern English word 'unsightliness.'

Initially, it meant 'not pleasing to the eye,' and this meaning has largely remained the same in modern usage.