'ungrateful' originates from Middle English, specifically the word 'ungratefull', where 'un-' meant 'not' and 'grateful' meant 'thankful'.

'ungratefull' changed from the Middle English word 'ungratefull' and eventually became the modern English word 'ungrateful'.

Initially, it meant 'not thankful', and this meaning has largely remained the same in modern usage.