'dud' (plural 'duds') originates from Middle English, specifically the word 'dudde', where 'dudde' meant 'a cloak or rag'.

'dud' changed from the Middle English word 'dudde' (meaning a cloak or rag) and later came into modern English as 'dud'; the plural form 'duds' developed as slang for clothes.

Initially, it meant 'a cloak or rag', but over time it evolved into 'clothes' (colloquial) and also developed the sense 'worthless thing' or 'failure' (e.g., a nonfunctional explosive).