colloquialism vs mouthpiece

colloquialism and mouthpiece both are nouns.

Word	Noun	Adjective	Verb	Adverb
colloquialism	Yes	No	No	No
mouthpiece	Yes	No	No	No

colloquialism (noun)	mouthpiece (noun)
a colloquial expression; characteristic of spoken or written communication that seeks to imitate informal speech	the aperture of a wind instrument into which the player blows directly
	the tube of a pipe or cigarette holder that a smoker holds in the mouth
	an acoustic device; the part of a telephone into which a person speaks
	(especially boxing) equipment that protects an athlete's mouth
	a part that goes over or into the mouth of a person
	a spokesperson (as a lawyer)