Acting like a wild dingo (5)
I believe the answer is:
doing
'acting' is the definition.
(I know that acting can be written as doing)
'wild dingo' is the wordplay.
'wild' is an anagram indicator.
'dingo' with letters rearranged gives 'DOING'.
'like a' is the link.
(Other definitions for doing that I've seen before include "Working" , "deed?" , "Hoaxing" , "Engaged in -- active" , "Execution" .)