Disgusting thing on the highway exit (4-3)
I believe the answer is:
turn-off
This clue could be a double definition.
'disgusting thing' is the first definition.
(something that disgusts someone or turns them off)
'the highway exit' is the second definition.
'turn off' can be an answer for 'exit' (a road). I'm not certain of the 'the highway' bit.
'on' acts as a link.
Can you help me to learn more?
(Other definitions for turn-off that I've seen before include "Something eliciting distaste" , "Something generating distaste" .)