'reincarcerate' originates from Latin elements, specifically the prefix 're-' meaning 'again' and 'incarcerare' (from 'carcer') meaning 'to imprison' or 'prison'.

'reincarcerate' was formed in modern English by adding the prefix 're-' to the verb 'incarcerate', which itself comes from Late Latin 'incarcerare' (from Latin 'carcer' meaning 'prison') and entered English via Medieval/Late Latin and French influence.

Initially the root 'incarcerare' meant 'to imprison'; with the addition of the prefix 're-' the modern word came to mean specifically 'to imprison again'.