Shouts “Goodbye” (6)
I believe the answer is:
cheers
I believe this is a double definition.
'shouts' is the first definition.
(I have seen 'Shouts of approval ' mean 'cheers' so perhaps 'shouts' could also mean 'cheers')
'goodbye' is the second definition.
(I know that goodbye can be written as cheers)
(Other definitions for cheers that I've seen before include "Bottoms up; thanks" , "so long and > much appreciated" , "Comforts" , "Ta; gives comfort to" , "A colloquial toast - hooray!" .)