'agonise' originates from Greek, specifically the word 'agōnizesthai,' where 'agōn' meant 'contest' or 'struggle.'

'agōnizesthai' transformed into the Late Latin word 'agonizare,' and eventually became the modern English word 'agonise' through Middle English.

Initially, it meant 'to compete or struggle,' but over time it evolved into its current meaning of 'to suffer or worry intensely.'