Is such jazz not quite the business? (4)
I believe the answer is:
trad
'is such jazz' is the definition.
I can't judge whether this defines the answer.
'not quite the business?' is the wordplay.
'not quite' means to remove the last letter.
'the business?' becomes 'trade' (trade is a kind of business).
'trade' with its final letter taken off is 'TRAD'.
Can you help me to learn more?
(Other definitions for trad that I've seen before include "Classical (abbr)" , "Style of jazz" , "Form of folk or jazz" , "Type of jazz or folk" , "music" .)