'trustworthy' originates from Old English, specifically the word 'trēowþ', where 'trēow' meant 'faith' and '-þ' was a suffix indicating a state or condition. 'Complete' originates from Latin, specifically the word 'complētus', where 'com-' meant 'together' and 'plēre' meant 'to fill'.

'trustworthy' changed from the Old English word 'trēowþ' and eventually became the modern English word 'trustworthy'. 'Complete' transformed from the Latin word 'complētus' and eventually became the modern English word 'complete' through Middle English.

Initially, 'trustworthy' meant 'worthy of trust or confidence', and this meaning has largely remained the same in modern usage. 'Complete' initially meant 'to fill up' and evolved into its current meaning of 'finished or concluded'.