Maybe crossroads where Jack gets oil (8)
I believe the answer is:
junction
'maybe crossroads' is the definition.
I can't tell whether this defines the answer.
'jack gets oil' is the wordplay.
'jack' becomes 'J' (playing card abbreviation).
'gets oil' becomes 'unction' (I can't explain this - if you can you should believe this answer much more).
'j'+'unction'='JUNCTION'
'where' is the link.
Can you help me to learn more?
(Other definitions for junction that I've seen before include "Intersection" , "turn-off" , "Box ---, no-waiting road area" , "Bhowani ---, novel/film; joint" , "Confluence" .)