slip road vs route

slip road and route both are nouns.

Word	Noun	Adjective	Verb	Adverb
slip road	Yes	No	No	No
route	Yes	No	Yes	No

As nouns, route is a hypernym of slip road; that is, route is a word with a broader meaning than slip road:

Other hypernyms of slip road include road.

slip road (noun)	route (noun)
a short road giving access to an expressway	an open way (generally public) for travel or transportation
	an established line of travel or access

slip road (verb)	route (verb)
	send via a specific route
	divert in a specified direction
	send documents or materials to appropriate destinations