Go in among salesmen terrified (5)
I believe the answer is:
enter
'go in' is the definition.
('enter' can be a synonym of 'go in')
'among salesmen terrified' is the wordplay.
'among' indicates a hidden word.
'ENTER' can be found hidden inside 'salesmen terrified'.
(Other definitions for enter that I've seen before include "Come/go in" , "Make a record of" , "Take part in a contest" , "Come in - register" , "Enrol" .)