'indispensable' originates from Medieval Latin, specifically the word 'indispensabilis,' where 'in-' meant 'not' and 'dispensabilis' meant 'able to be dispensed with.'

'indispensabilis' transformed into the French word 'indispensable,' and eventually became the modern English word 'indispensable' through Middle English.

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