pugilism vs mouthpiece

pugilism and mouthpiece both are nouns.

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

pugilism (noun)	mouthpiece (noun)
fighting with the fists	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)