Novel flourish in music genre (3,4)
I believe the answer is:
new wave
'music genre' is the definition.
Although both the answer and definition are singular nouns, I don't see how one could define the other.
'novel flourish' is the wordplay.
'novel' becomes 'new' (synonyms).
'flourish' becomes 'wave' (synonyms).
'new'+'wave'='NEW WAVE'
'in' is the link.
Can you help me to learn more?
(Other definitions for new wave that I've seen before include "1970s rock style" , "Style of rock music deriving from punk" .)