'overconfident' originates from the prefix 'over-' meaning 'excessively' and the word 'confident' from Latin 'confidere', where 'con-' meant 'with' and 'fidere' meant 'to trust'.

'confidere' transformed into the Old French word 'confident', and eventually became the modern English word 'confident'. The prefix 'over-' was added to form 'overconfident'.

Initially, 'confident' meant 'trusting in oneself', but with the prefix 'over-', it evolved to mean 'excessively trusting in oneself'.