brake light vs stoplight

brake light and stoplight both are nouns.

Word	Noun	Adjective	Verb	Adverb
brake light	Yes	No	No	No
stoplight	Yes	No	No	No

As nouns, brake light and stoplight are synonyms defined as:

brake light and stoplight: a red light on the rear of a motor vehicle that signals when the brakes are applied to slow or stop

brake light (noun)	stoplight (noun)
a red light on the rear of a motor vehicle that signals when the brakes are applied to slow or stop	a visual signal to control the flow of traffic at intersections
	a red light on the rear of a motor vehicle that signals when the brakes are applied to slow or stop