'esoteric' originates from Greek, specifically the word 'esōterikos,' where 'esō' meant 'within.'

'esōterikos' transformed into the Latin word 'esotericus,' and eventually became the modern English word 'esoteric' through Middle English.

Initially, it meant 'pertaining to the inner circle,' but over time it evolved into its current meaning of 'understood by a select few.'