Tanker (5)
I believe the answer is:
oiler
'tanker' is the definition.
(I know that tanker can be written as oiler)
This is all the clue.
(Other definitions for oiler that I've seen before include "It carries fuel" , "Chippendales assistant?" , "Loire (anag.)" , "One applying lubricant" , "Device that lubricates" .)