'preprostatic' is formed from the prefix 'pre-' (from Latin 'prae' meaning 'before') combined with 'prostatic' (from Neo-Latin 'prostaticus').

'prostatic' derives from Greek 'prostátēs' (προστάτης) meaning 'one who stands before'; this passed into Late/Neo-Latin as 'prostaticus' and into English as 'prostatic'. The modern compound 'preprostatic' was formed in medical usage by adding the Latin prefix 'pre-' to 'prostatic'.

Initially the Greek root conveyed the sense of 'standing before'; in anatomy it came to denote the organ 'prostate' and related positions. The compound 'preprostatic' specifically means 'situated before the prostate' and retains that anatomical sense.