taillight vs rear light

taillight and rear light both are nouns.

Word	Noun	Adjective	Verb	Adverb
taillight	Yes	No	No	No
rear light	Yes	No	No	No

As nouns, taillight and rear light are synonyms defined as:

taillight and rear light: lamp (usually red) mounted at the rear of a motor vehicle

Other synonyms of taillight include rear lamp, tail lamp.

taillight (noun)	rear light (noun)
lamp (usually red) mounted at the rear of a motor vehicle	lamp (usually red) mounted at the rear of a motor vehicle