parking brake vs emergency brake

parking brake and emergency brake both are nouns.

Word	Noun	Adjective	Verb	Adverb
parking brake	Yes	No	No	No
emergency brake	Yes	No	No	No

As nouns, parking brake and emergency brake are synonyms defined as:

parking brake and emergency brake: a brake operated by hand; usually operates by mechanical linkage

Other synonyms of parking brake include emergency, hand brake.

parking brake (noun)	emergency brake (noun)
a brake operated by hand; usually operates by mechanical linkage	a brake operated by hand; usually operates by mechanical linkage