Retro music in curry house, say, that enhances meal (4)
I believe the answer is:
agar
'in curry house say that enhances meal' is the definition.
The definition and answer can be both substances as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'retro music' is the wordplay.
'retro' shows that the letters should be reversed in order (retro is Latin for 'backwards').
'music' becomes 'raga' (I have seen 'Indian music' mean 'raga' so perhaps 'music' could also mean 'raga').
'raga' back-to-front is 'AGAR'.
Can you help me to learn more?
(Other definitions for agar that I've seen before include "Food-thickening jelly" , "Jelly used in bacteria culture" , "Jelly medium" , "Medium for growth" , "Jelly got from seaweeds, used in foods" .)