Axle or elbow? (6)

I believe the answer is:
grease
(Other definitions for grease that I've seen before include "Musical - lubricant" , "Travolta's 1978 film" , "Musical animal fat?" , "Fully aware, astonished" , "bribe" .)
I believe the answer is:
grease
(Other definitions for grease that I've seen before include "Musical - lubricant" , "Travolta's 1978 film" , "Musical animal fat?" , "Fully aware, astonished" , "bribe" .)