'irrefutable' originates from Latin, specifically the word 'irrefutabilis,' where 'in-' meant 'not' and 'refutare' meant 'to repel or refute.'

'irrefutabilis' transformed into the French word 'irréfutable,' and eventually became the modern English word 'irrefutable' through Middle English.

Initially, it meant 'not able to be refuted,' and this meaning has largely remained the same in modern usage.