'sura' (Qur'anic sense) originates from Arabic, specifically the word 'sūrah' (سورة), where 'sūrah' meant 'chapter' or 'a division of the scripture'. The anatomical sense 'sura' originates from Latin, specifically the word 'sūra', where 'sūra' meant 'calf of the leg'.

'sura' (from Arabic 'sūrah') entered English via transliteration and religious scholarship (often seen as 'surah' or 'sura') from Arabic in modern times; the anatomical 'sura' passed into English from Latin (and New Latin/medical usage) through medieval and early modern anatomical texts.

The Arabic-derived sense initially referred specifically to a division of the Qur'an and has retained that meaning in English; the Latin-derived anatomical sense originally referred to the 'calf' and has likewise remained specialized in medical/anatomical use.