Put tar over back section of snare (3,4)
I believe the answer is:
rat trap
'put' is the definition.
I know nothing about this answer so I can't tell whether this works.
'tar over back section of snare' is the wordplay.
I cannot really see how this works, but
an anagram of 'tar' is 'rat' which is within the answer.
'snare' could be 'trap' (synonyms) and 'trap' is found in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for rat trap that I've seen before include "in which pest caught" , "might this stop his desertion?" , "rodent catcher" , "foothold" , "Rodent-catcher" .)