'anteroexternal' originates from the combining form 'antero-' (from Latin 'ante', meaning 'before, in front of') together with English 'external' (from Latin 'externus', meaning 'outer').

'anteroexternal' was formed in modern medical/technical English by joining the prefix 'antero-' (from Latin 'ante') to the adjective 'external' (from Latin 'externus'), appearing as 'antero-external' in usage and later written as the single word 'anteroexternal'.

Initially it meant 'relating to the front and outer surface' in anatomical description, and this specific anatomical sense has remained stable.