emergency brake vs parking brake

emergency brake and parking brake both are nouns.

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

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

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

Other synonyms of emergency brake include emergency, hand brake.

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