Long line of cars? (5)
I believe the answer is:
cable
'long line' is the definition.
'cable' can be an answer for 'line' (I have seen 'Strong line' mean 'cable' so perhaps 'line' could also mean 'cable'). I am not sure about the 'long' bit.
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for cable that I've seen before include "Wire, flex" , "Satellite alternative?" , "Naut. length; transmit" , "Strong suspension bridge made of wire" , "Rope for communication" .)