'apple-tree' originates from Old English, specifically the words 'æppel' and 'trēow', where 'æppel' meant 'apple' and 'trēow' meant 'tree'.

'apple-tree' changed from Old English compound 'æppeltrēow' and Middle English forms such as 'appel-tre'/'appel-treow', and eventually became the Modern English 'apple-tree'.

Initially it meant 'a tree bearing apples', and over time it has retained that core meaning in modern usage.