Pine resin has the top left off (4)
I believe the answer is:
itch
'pine' is the definition.
(to pine for and to itch for both mean to desire)
'resin has the top left off' is the wordplay.
I cannot quite understand how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found within the answer.
The remaining letters 'ich' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for itch that I've seen before include "It must be scratched" , "Uncomfortable feeling" , "Yearn" , "A nagging desire" , "Skin sensation; desire" .)