French city associated with Bill Sikes (5)

I believe the answer is:

nancy

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'french city' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for nancy that I've seen before include "Girl; French city" , "Dickensian character who died" , "City in Lorraine" , "Dickensian murder victim - city in northeast France" , "Dickensian heroine" .)

I've seen this clue in the Evening Standard.

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