'isotropic' originates from Greek, specifically the elements 'isos' and 'tropos', where 'isos' meant 'equal' and 'tropos' meant 'turn, direction'.

'isotropic' developed in scientific usage via New Latin/Modern scientific coinage (e.g. New Latin 'isotropicus') and forms in French ('isotrope'), and eventually became the modern English adjective 'isotropic' and the adverb 'isotropically'.

Initially, it meant 'having equal properties in all directions', and over time this core meaning has been retained in current usage.