Leave rubbish uncovered (3,2)
I believe the answer is:
got at
'uncovered' is the definition.
Although both the answer and definition are past participle verbs, I don't see how one could define the other.
'leave rubbish' is the wordplay.
'leave' becomes 'go' (to go is to depart or leave).
'rubbish' becomes 'tat' (low-quality items or material).
'go'+'tat'='GOT AT'
Can you help me to learn more?
(Other definitions for got at that I've seen before include "Nobbled" , "Unfairly influenced" , "Criticised" , "Attacked verbally" .)