What a drifter will do, making love flat out (5)
I believe the answer is:
float
'what a drifter will do' is the definition.
The definition suggests a singular noun which matches the answer.
'love flat out' is the wordplay.
'love' becomes 'o' (love means zero in tennis).
'out' means one lot of letters goes inside another.
'o' put into 'flat' is 'FLOAT'.
'making' is the link.
Can you help me to learn more?
(Other definitions for float that I've seen before include "Carnival display" , "Put forward (an idea)" , "Money in hand" , "Rest on the surface of a fluid" , "bread supply?" .)