'prefatory' originates from Latin, specifically the word 'praefatorius,' where 'prae-' meant 'before' and 'fari' meant 'to speak.'

'praefatorius' transformed into the French word 'préfacier,' and eventually became the modern English word 'prefatory' through Middle English.

Initially, it meant 'spoken before,' but over time it evolved into its current meaning of 'serving as an introduction or preface.'