'defoliate' originates from Latin, specifically the verb 'defoliare', where the prefix 'de-' meant 'off' or 'away' and 'folium' meant 'leaf'.

'defoliate' changed from the Late Latin word 'defoliare' into Old French forms such as 'défolier' and eventually became the modern English word 'defoliate'.

Initially, it meant 'to strip or remove leaves', and over time it has retained that basic meaning in modern English.