This could start you off on the slippery slope (3,4)
I believe the answer is:
ski lift
'this could start you off on the slippery slope' is the definition.
The definition suggests a singular noun which matches the answer.
This is all the clue.
Can you help me to learn more?
(Other definitions for ski lift that I've seen before include "Device for carrying winter sports enthusiasts" , "It can help you get up at Aviemore" , "Way to the top" , "Winter sports elevator" , "Winter sports facility" .)