Footpath legislation backed by King (4)
I believe the answer is:
walk
'footpath' is the definition.
(thesaurus)
'legislation backed by king' is the wordplay.
'legislation' becomes 'law' (I've seen this before).
'backed' says the letters should be written backwards.
'by' is a charade indicator (letters next to each other).
'king' becomes 'K' (chess abbreviation).
'law' back-to-front is 'wal'.
'wal'+'k'='WALK'
(Other definitions for walk that I've seen before include "Stretch one's legs" , "Stroll" , "Go on foot" , "Perambulate" , "Ramble" .)