'unhappily' originates from the Old English prefix 'un-' meaning 'not' and the word 'happy' from Middle English 'hap,' meaning 'chance' or 'luck.'

'unhappy' changed from the Middle English word 'unhappi' and eventually became the modern English word 'unhappy.'

Initially, it meant 'not lucky,' but over time it evolved into its current meaning of 'not happy.'