Girl's name for a French city (5)
I believe the answer is:
nancy
'for a french city' is the definition.
(city in France)
'girl's name' is the wordplay.
'girl' becomes 'Nan' (short for Nancy or Ann).
'name' becomes 'cy' ().
'nan'+'cy'='NANCY'
(Other definitions for nancy that I've seen before include "one of the Mitford sisters" , "Dickensian character who died" , "City in Lorraine" , "Dickensian murder victim - city in northeast France" , "No Man" .)