General acceptance of Mark e.g. in the past (8)

I believe the answer is:

currency

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'general acceptance' is the definition.
(I've seen this before)

I don't understand how the rest of the clue works.

(Other definitions for currency that I've seen before include "Bread" , "General acceptance" , "euro?" , "Legal tender" , "System of money in general use" .)

I've seen this clue in The Telegraph.

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