'anisometropic' originates from Greek-derived medical formation, specifically the prefix 'aniso-' from Greek 'anisos' meaning 'unequal' and the element 'metropia'/'metron' from Greek 'metron' meaning 'measure', combined with the adjective-forming suffix '-ic' (via Neo-Latin/medical English).

'anisometropic' developed as an adjective from the noun 'anisometropia' (Neo-Latin/medical term), which itself was formed from Greek elements and entered English medical usage; the adjective form was later derived to describe conditions or patients exhibiting anisometropia.

Originally the Greek elements conveyed the idea of 'unequal measure'; over time the compound specialized in medicine to mean specifically 'unequal refractive power between the two eyes', and 'anisometropic' came to describe persons or conditions exhibiting that ocular inequality.