Correct, labyrinthine route north of Switzerland (7)
I believe the answer is:
retouch
'correct' is the definition.
(thesaurus)
'labyrinthine route north of switzerland' is the wordplay.
'labyrinthine' indicates anagramming the letters (labyrinthine can mean complex or convoluted).
'north of' is a charade indicator (letters next to each other) (in a down clue, some letters go above others).
'switzerland' becomes 'ch' (short for Confoederatio Helvetica, its Latin name).
'route' anagrammed gives 'retou'.
'retou'+'ch'='RETOUCH'
(Other definitions for retouch that I've seen before include "Repair a painting" , "Correct painting" , "Fine-tune" , "Paint over" , "Improve a photo, with a pencil say" .)