Beauty parlour with built-in love lounge (6)
I believe the answer is:
saloon
'lounge' is the definition.
(I've seen this before)
'beauty parlour with built-in love' is the wordplay.
'beauty parlour' becomes 'salon' (synonyms).
'with' is an insertion indicator.
'built-in love' becomes 'o' (love means zero in tennis. I am not sure about the 'built-in' bit.).
'salon' placed around 'o' is 'SALOON'.
Can you help me to learn more?
(Other definitions for saloon that I've seen before include "Describing a bar - describing a car" , "Lounge bar" , "Bar or shape of car" , "Large public room" , "Bar room" .)