A wound mark permitted to be red! (7)
I believe the answer is:
scarlet
'be red' is the definition.
(synonyms)
'a wound mark permitted' is the wordplay.
'a wound mark' becomes 'scar' (I've seen this before).
'permitted' becomes 'let' (to let something happen is to permit it).
'scar'+'let'='SCARLET'
'to' acts as a link.
(Other definitions for scarlet that I've seen before include "immoral" , "bloody?" , "Cherry-red" , "Vivid red" , "Murderer" .)