Cover outlet about the end of winter (4)
I believe the answer is:
tarp
'cover' is the definition.
(I've seen this before)
'outlet about the end of winter' is the wordplay.
'outlet' becomes 'tap' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'about' is an insertion indicator.
'the end of' says to take the final letters.
The final letter of 'winter' is 'r'.
'tap' going around 'r' is 'TARP'.
Can you help me to learn more?
(Other definitions for tarp that I've seen before include "Cover" , "canvas sheet" , "Bail-out" .)