A bundle of nerves after the business talk (8)
I believe the answer is:
converse
'talk' is the definition.
(conversing is a kind of talking)
'a bundle of nerves after the business' is the wordplay.
'a bundle of' indicates anagramming the letters (I've seen 'bundle' mean this).
'after' means one lot of letters go next to another.
'the business' becomes 'co' (**).
'nerves' anagrammed gives 'nverse'.
'nverse' put after 'co' is 'CONVERSE'.
(Other definitions for converse that I've seen before include "Talk together" , "Opposing" , "Quite the opposite!" , "Turned round" , "express thoughts and ideas?" .)