Rolling account left unpaid (9)

I believe the answer is:

billowing

'rolling' is the definition.
(thesaurus)

'account left unpaid' is the wordplay.
'account' becomes 'bill' (synonyms).
'left unpaid' becomes 'owing' (as in unpaid bills).
'bill'+'owing'='BILLOWING'

(Other definitions for billowing that I've seen before include "rolling in" , "affected by inflation" .)

I've seen this clue in The Times.

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