'isotropicness' originates from English, specifically formed by adding the noun-forming suffix '-ness' to the adjective 'isotropic', which ultimately comes from New Latin/Greek where 'iso-' meant 'equal' and 'tropos' meant 'turn'.

'isotropic' entered scientific English from New Latin/Greek 'isotropus' / 'isotropes' (Greek 'isos' + 'tropos'); the abstract noun 'isotropy' and the adjective 'isotropic' were established in scientific usage, and later English formed the derived noun 'isotropicness' by combining 'isotropic' + '-ness'.

Initially the Greek-rooted term described 'having the same properties in every direction'; over time the scientific meanings ('isotropy'/'isotropic') were preserved, and the suffix '-ness' simply produced the noun denoting that quality ('isotropicness').