Covered by maid, ledge gathering dust (4)

I believe the answer is:

idle

'gathering dust' is the definition.
(something gathering dust is idle or unused)

'covered by maid ledge' is the wordplay.
'covered by' indicates a hidden word.
'IDLE' is hidden within 'maid ledge'.

(Other definitions for idle that I've seen before include "Circus entertainer" , "Loaf" , "Empty" , "Useless" , "Fruitless" .)

I've seen this clue in The Guardian.

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