'wudu' originates from Arabic, specifically the word 'وضوء' (wudūʼ), where 'وضوء' meant 'purification or cleanliness'.

'وضوء' (wudūʼ) was adopted into English as 'wudu' to describe the Islamic ritual of purification.

Initially, it meant 'purification or cleanliness', and this meaning has largely remained the same in modern usage.