. . . covered in oil perhaps, not naked (7)
I believe the answer is:
dressed
'covered' is the definition.
('dress' can be a synonym of 'cover')
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for dressed that I've seen before include "Wearing clothes" , "as a crab may be?" , "Clothed" , "finery?" , "Applied manure to garden" .)