Lady love is after the money (4)
I believe the answer is:
lois
'lady' is the definition.
'love is after the money' is the wordplay.
'love' becomes 'o' (In tennis, 'love' means 'zero').
'after' says to put letters next to each other.
'the money' becomes 'l' (L can mean 'pounds'**).
'o'+'is'='ois'
'ois' put after 'l' is 'LOIS'.
(Other definitions for lois that I've seen before include "Superman's girlfriend" , "- Lane (Superman's girl)" , "- Lane, Daily Planet reporter" , "-- Lane, 'Superman' character" , "Woman" .)