Pig on loose trampled over top of trimmed grass (5,6)
I believe the answer is:
stool pigeon
'grass' is the definition.
(I've seen this before)
'pig on loose trampled over top of trimmed' is the wordplay.
I cannot quite see how this works, but
'on' could be 'to' and 'to' is present in the answer.
'over' could be 'on' (physically on top of) and 'on' is located in the answer.
'of' could be 'o' and 'o' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for stool pigeon that I've seen before include "Police informer" , "Grass" .)