'defectiveness' originates from Latin, specifically the word 'defectus,' where 'de-' meant 'down from' and 'facere' meant 'to do or make.'

'defectus' transformed into the Old French word 'defect,' and eventually became the modern English word 'defectiveness' through Middle English.

Initially, it meant 'a failing or deficiency,' but over time it evolved into its current meaning of 'the state of having a defect or flaw.'