Elephant on edge, or some injury on top of trunks (5)
I believe the answer is:
torsi
'trunks' is the definition.
('torso' can be a synonym of 'trunk')
'elephant on edge or some injury on top' is the wordplay.
'elephant on edge' becomes 't' (I can't explain this - if you can you should believe this answer much more).
'on top' indicates taking the first letters.
The initial letters of 'some injury' is 'si'.
't'+'or'+'si'='TORSI'
'of' is the link.
Can you help me to learn more?
(Another definition for torsi that I've seen is " Rare parts of statues".)