Round of applause or gunfire (5)
I believe the answer is:
salvo
This clue is a double definition.
'round of applause' is the first definition.
(I've seen this in another clue)
'gunfire' is the second definition.
(I've seen this in another clue)
(Other definitions for salvo that I've seen before include "reservation" , "Simultaneous firing of weapons" , "saving clause" , "Simultaneous discharge of guns" , "A simultaneous salute of guns" .)