'obligatory' originates from Latin, specifically the word 'obligatorius,' where 'ob-' meant 'toward' and 'ligare' meant 'to bind.'

'obligatorius' transformed into the Old French word 'obligatoire,' and eventually became the modern English word 'obligatory' through Middle English.

Initially, it meant 'to bind or tie,' but over time it evolved into its current meaning of 'required or compulsory.'