Flash bum around heads of HSBC in High Barnet (7)
I believe the answer is:
mohican
'high barnet' is the definition.
The definition suggests a singular noun which matches the answer.
'flash bum around heads of hsbc in' is the wordplay.
'flash' becomes 'mo' (both mean a very short period of time).
'bum' becomes 'can' (synonyms).
'around' means one lot of letters goes inside another.
'heads of' suggests taking the first letters.
The initial letters of 'hsbc in' is 'hi'.
'mo'+'can'='mocan'
'mocan' enclosing 'hi' is 'MOHICAN'.
Can you help me to learn more?
(Other definitions for mohican that I've seen before include "striking style" , "elevated style" , "Haircut with only a band of hair down the middle of the scalp" , "type of cut" , "Hairstyle with a tall, spiky wall of hair, shaved either side" .)