'irrespective' originates from the Latin word 'respectus', where 're-' meant 'back' and 'specere' meant 'to look'.

'respectus' transformed into the English word 'respect', and eventually became the modern English word 'irrespective' by adding the prefix 'ir-' to indicate negation.

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