Spare personal injury (4)
I believe the answer is:
gash
This might be a double definition.
'spare' is the first definition.
(I've seen this before)
'personal injury' is the second definition.
'gash' can be an answer for 'injury' (gash is a kind of injury). I am not sure about the 'personal' bit.
Can you help me to learn more?
(Other definitions for gash that I've seen before include "Open wound" , "Unnecessary" , "Deep, jagged tear" , "score heavily" , "Ghastly" .)