'amenorrhoea' originates from Greek, specifically the word 'amenorrhoia,' where 'a-' meant 'without,' 'men' referred to 'month,' and 'rhoia' meant 'flow.'

'amenorrhoia' transformed into the Latin word 'amenorrhoea,' and eventually became the modern English word 'amenorrhoea.'

Initially, it meant 'without monthly flow,' and this meaning has largely remained the same in modern usage.