Shout around a tree (4)
I believe the answer is:
bark
'shout' is the definition.
(thesaurus)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for bark that I've seen before include "Shout aggressively" , "Cry of a dog or fox" , "Hardly a sound from Tom" , "give sharp cry" , "Woof" .)