'hemianopsia' originates from Modern medical coinage (New Latin/International scientific vocabulary), specifically formed from Greek elements: 'hēmi-' meaning 'half' and 'an-opsia'/'opsia' relating to 'sight'.

'hemianopsia' was formed in modern medical terminology from Greek components (hēmi- + opsia). The Greek roots entered medical Latin/modern English usage via New Latin and international medical vocabulary rather than through an intervening common-language form.

Initially it meant 'half blindness' (literally 'half-sightless'), and this core sense has persisted; in modern clinical use it refers more precisely to loss of half the visual field, often with subtypes (e.g., homonymous hemianopsia).