Goldcrest surgically gutted — it should establish cause of death (7)
I believe the answer is:
autopsy
'death' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Perhaps you can see a link between them that I can't see?
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for autopsy that I've seen before include "Far from quick examination" , "Pays out (anag.)" , "PM" , "final examination" , "Examination after death, a post-mortem" .)