They run out of clothes (9)

I believe the answer is:

streakers

'they' is the definition.
Both the answer and definition are plural nouns.
Maybe you can see a link between them that I can't see?

'run out of clothes' is the wordplay.
'run' becomes 'streak' (synonyms).
'out of clothes' becomes 'ers' (I can't explain this - if you can you should give a lot more credence to this answer).
'streak'+'ers'='STREAKERS'

(Another definition for streakers that I've seen is " They run naughtily nude".)

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