Wound’s mark (4)
I believe the answer is:
scar
'wound's mark' is the definition.
'scar' can be an answer for 'mark' (mark left by an injury). I also know that 'wound' relates to this answer.
This is the entire clue.
(Other definitions for scar that I've seen before include "Long (for)" , "Indication of damage" , "Sign of old injury" , "Mark on body or tree" , "Fish" .)