Country abandoning European currency (5)

I believe the answer is:

franc

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'currency' is the definition.
(old French currency)

I don't understand the rest of the clue.

(Other definitions for franc that I've seen before include "Foreign currency" , "Former French currency" , "Old French money" , "Unit of money" , "It's ready" .)

I've seen this clue in The Times.

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