To grease it means hard work (5)
I believe the answer is:
elbow
This could be a double definition.
'to grease' is the first definition.
The answer and definition can be both to do with contact as well as being verbs in their base form.
Maybe you can see an association between them that I can't see?
'hard work' is the second definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'it means' acts as a link.
Can you help me to learn more?
(Other definitions for elbow that I've seen before include "sharp turn" , "Jostle" , "part of the body" , "Arm joint, more power to it" , "Reject" .)