Married a French lady -- this is how to greet her (6)
I believe the answer is:
madame
'this is how to greet her' is the definition.
(term of address for a French woman)
'married a french lady' is the wordplay.
'married' becomes 'm'.
'french lady' becomes 'dame' ('lady' in French).
'm'+'a'+'dame'='MADAME'
(Other definitions for madame that I've seen before include "Married woman abroad" , "Flaubert novel" , "Woman of refinement" , "Married woman in Montpellier?" , "French married woman" .)