'disciplinary' originates from Latin, specifically the word 'disciplinarius,' where 'disciplina' meant 'instruction or knowledge.'

'disciplinarius' transformed into the Old French word 'disciplinarie,' and eventually became the modern English word 'disciplinary' through Middle English.

Initially, it meant 'related to instruction or knowledge,' but over time it evolved into its current meaning of 'related to the enforcement of rules or order.'