'arrhythmia' originates from Greek, specifically the word 'arrhythmos,' where 'a-' meant 'without' and 'rhythmos' meant 'rhythm.'

'arrhythmos' transformed into the Latin word 'arrhythmia,' and eventually became the modern English word 'arrhythmia.'

Initially, it meant 'without rhythm,' but over time it evolved into its current meaning of 'irregular heartbeat.'