Lamp oil (8)
I believe the answer is:
kerosene
'lamp oil' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for kerosene that I've seen before include "Sore knee (anag.)" , "Paraffin oil (E, not I)" , "Combustible" , "No seeker for American fuel oil" , "Oil used as fuel in lamps and heaters" .)