'antesternal' originates from Latin elements: the prefix 'ante-' meaning 'before' and 'sternal' derived from Latin 'sternum' meaning 'breastbone'.

'antesternal' was formed in Late/Neo-Latin/English by combining Latin 'ante-' + 'sternum' (itself from Greek 'sternon' meaning 'chest'), producing a medical adjective used in anatomical descriptions.

Initially it meant 'located before the sternum', and this core anatomical meaning has remained essentially unchanged in medical usage.