Many trousers briefly removed (4,2)

I believe the answer is:

bags of

'many' is the definition.
(both can mean large amounts)

'trousers briefly removed' is the wordplay.
'trousers' becomes 'bags' (informal term for trousers, Oxford bags).
'briefly' means to remove the last letter.
'removed' becomes 'off' (as in an item of clothing taken off).
'off' with its last letter taken away is 'of'.
'bags'+'of'='BAGS OF'

I've seen this clue in The Guardian.

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