'trustworthy' originates from Middle English, combining 'trust' from Old Norse 'traust' meaning 'confidence' and 'worthy' from Old English 'weorþe' meaning 'valuable'.

'trustworthy' evolved from the Middle English word 'trustworthi', which combined 'trust' and 'worthi', eventually becoming the modern English word 'trustworthy'.

Initially, it meant 'worthy of trust', and this meaning has largely remained the same in modern usage.