Woman earned about a million (6)
I believe the answer is:
madame
'woman' is the definition.
(used to address a woman)
'earned about a million' is the wordplay.
'earned' becomes 'made' ('make' can be a synonym of 'earn').
'about' means one lot of letters goes inside another.
'million' becomes 'm' (abbreviation).
'a'+'m'='am'
'made' enclosing 'am' is 'MADAME'.
(Other definitions for madame that I've seen before include "French Mrs" , "Book by Flaubert" , "Married woman in Montpellier?" , "Married woman abroad" , "Title for a Frenchwoman" .)