Bill about a land measure (4)

I believe the answer is:

acre

'a land measure' is the definition.
(I've seen this before)

'bill about' is the wordplay.
'bill' becomes 'ac' (abbreviation for account).
'about' becomes 're' ('re' means regarding or about).
'ac'+'re'='ACRE'

(Other definitions for acre that I've seen before include "Old unit of area - old port" , "Muslims here besieged" , "Imperial unit of area" , "Imperial land measurement" , "Unit of land measurement" .)

I've seen this clue in The Globe and Mail.

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