toll road vs turnpike

toll road and turnpike both are nouns.

Word	Noun	Adjective	Verb	Adverb
toll road	Yes	No	No	No
turnpike	Yes	No	No	No

As nouns, toll road and turnpike are synonyms defined as:

toll road (noun)	turnpike (noun)
an expressway on which tolls are collected	an expressway on which tolls are collected
	(from 16th to 19th centuries) gates set across a road to prevent passage until a toll had been paid