'exotropia' originates from New Latin/medical Latin, ultimately from Greek, specifically the elements 'exō-' (from Greek 'exō', meaning 'outside') and 'tropē' (from Greek 'trope', meaning 'a turning').

'exotropia' was formed in New Latin as 'exotropia' from the Greek elements 'exō' + 'tropē' and entered English medical vocabulary in the late 19th century as 'exotropia'.

Initially, it meant 'outward turning' (of the eye), and over time it has retained that specific medical meaning of 'outward deviation of an eye'.