Feature of Dartmoor — rubbish thrown around (3)
I believe the answer is:
tor
'feature of dartmoor' is the definition.
(I've seen this before)
'rubbish thrown around' is the wordplay.
'rubbish' becomes 'rot' (both can mean nonsense).
'thrown around' shows that the letters should be reversed in order.
'rot' in reverse letter order is 'TOR'.
(Other definitions for tor that I've seen before include "Rocky height, eg Mam" , "Rot on a peak in Devon" , "Hill or rocky peak" , "fell" , "Rocky crag" .)