Folds worn-down hides (4,11)

I believe the answer is:

goes underground

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'hides' is the definition.
I know nothing about this answer so I can't judge whether this works.

'folds worn-down' is the wordplay.
'folds' becomes 'goes under' (I've seen this in another clue).
'worn down' becomes 'ground' (ground down).
'goesunder'+'ground'='GOES UNDERGROUND'

Can you help me to learn more?

I've seen this clue in The Telegraph.

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