'unapproachable' originates from the prefix 'un-' meaning 'not' and the word 'approachable', which comes from the Latin 'approchare', meaning 'to come near'.

'approchare' transformed into the Old French word 'aprochier', and eventually became the modern English word 'approach', with 'unapproachable' forming later.

Initially, 'approach' meant 'to come near', and 'unapproachable' evolved to mean 'not easy to approach or talk to'.