Trunk found in north-west or south-east (5)
I believe the answer is:
torso
'trunk' is the definition.
(both can mean a person's chest)
'north-west or south-east' is the wordplay.
'north' says the letters should be written backwards (in a down clue, letters go up or 'north').
'west' indicates taking the first letters (I've seen 'west of' mean this (most west - leftmost - letter)).
'east' becomes 'rot' (I can't justify this - if you can you should believe this answer much more).
The first letters of 'or south' is 'os'.
'os'+'rot'='osrot'
'osrot' back-to-front is 'TORSO'.
'found in' acts as a link.
Can you help me to learn more?
(Other definitions for torso that I've seen before include "Roots out in trunk of the body" , "Body without head, neck and limbs" , "Trunk; headless, limbless body" , "Roost on trunk?" , "Piece of bronze" .)