'zounds' originates from Middle English, specifically the phrase 'God's wounds', where 'God's' referred to the deity and 'wounds' referred to the wounds of Christ.

'God's wounds' transformed into the Middle English contraction 'zounds', and eventually became the modern English exclamation 'zounds'.

Initially, it meant 'by God's wounds', but over time it evolved into a general exclamation of surprise or indignation.