Red mark of damage on permit (7)
I believe the answer is:
scarlet
'red' is the definition.
(I know that scarlet is a type of red)
'damage on permit' is the wordplay.
'damage' becomes 'scar' (I've seen this before).
'on' says to put letters next to each other (in a down clue, letters appear on others).
'permit' becomes 'let' (synonyms).
'scar'+'let'='SCARLET'
'mark of' acts as a link.
This may not be correct. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for scarlet that I've seen before include "Cartels (anag.)" , "Colour of embarrassment?" , "Murderer" , "Shade of red" , "Let cars be this colour" .)