'hemianopia' originates from Greek-derived medical formation, specifically the elements 'hēmi-' and 'anōpia', where 'hēmi-' meant 'half' and 'anōpia' meant 'blindness'.

'hemianopia' entered medical Latin/New Latin from Greek 'hēmi-' + 'anōpia' and was adopted into English medical usage in the 19th century (variants such as 'hemianopsia' also appeared).

Initially, it meant 'half blindness' (loss of sight in half the visual field), and this core meaning has remained largely unchanged in modern medical usage.