engine cooling system vs radiator

engine cooling system and radiator both are nouns.

Word	Noun	Adjective	Verb	Adverb
engine cooling system	Yes	No	No	No
radiator	Yes	No	No	No

engine cooling system (noun)	radiator (noun)
equipment in a motor vehicle that cools the engine	a mechanism consisting of a metal honeycomb through which hot fluids circulate; heat is transferred from the fluid through the honeycomb to the airstream that is created either by the motion of the vehicle or by a fan
	heater consisting of a series of pipes for circulating steam or hot water to heat rooms or buildings
	any object that radiates energy