Authorised walk (14)
I believe the answer is:
constitutional
I believe this clue is a double definition.
'authorised' is the first definition.
(thesaurus)
'walk' is the second definition.
(I know that constitutional is a type of walk)
(Other definitions for constitutional that I've seen before include "in line with country code" , "Relating to a person's physical or mental state" , "authorised by the body politic" , "Governmental" , "Healthy steps taken" .)