'well-versed' originates from the combination of 'well,' meaning 'in a good or satisfactory way,' and 'versed,' which comes from the Latin word 'versatus,' meaning 'experienced or practiced.'

'versatus' transformed into the Old French word 'versé,' and eventually became the modern English word 'versed.'

Initially, it meant 'experienced or practiced,' and over time it evolved into its current meaning of 'having a lot of knowledge about something.'