'inadvertently' originates from Latin, specifically the word 'inadvertentem,' where 'in-' meant 'not' and 'advertentem' meant 'turning the mind to.' 'grant' originates from Old French, specifically the word 'graanter,' where 'graanter' meant 'to allow or permit.'

'inadvertentem' transformed into the English word 'inadvertent,' and eventually became 'inadvertently' in modern English. 'graanter' transformed into the English word 'grant' through Middle English.

Initially, 'inadvertently' meant 'not turning the mind to,' but over time it evolved into its current meaning of 'unintentionally.' 'grant' has largely retained its original meaning of 'to allow or permit.'