'equestrian' originates from Latin, specifically the word 'equestrianus,' where 'eques' meant 'horseman.'

'equestrianus' transformed into the Old French word 'equestrien,' and eventually became the modern English word 'equestrian.'

Initially, it meant 'related to horsemen,' but over time it evolved into its current meaning of 'relating to horse riding or a person who rides horses.'