Follow spoor (5)
I believe the answer is:
trail
I believe this is a double definition.
'follow' is the first definition.
(trail can mean to follow in secret)
'spoor' is the second definition.
(I've seen this before)
(Other definitions for trail that I've seen before include "Drag along the ground" , "Get behind" , "Follow - track" , "Spoor - lag behind" , "Track or scent used in following someone" .)