'diligent' originates from Latin, specifically the word 'diligentem,' where 'diligere' meant 'to value highly, to love.'

'diligentem' transformed into the Old French word 'diligent,' and eventually became the modern English word 'diligent' through Middle English.

Initially, it meant 'to value highly or love,' but over time it evolved into its current meaning of 'showing care and conscientiousness in one's work or duties.'