silencer vs muffler

silencer and muffler both are nouns.

Word	Noun	Adjective	Verb	Adverb
silencer	Yes	No	No	No
muffler	Yes	No	No	No

As nouns, silencer and muffler are synonyms defined as:

silencer and muffler: a tubular acoustic device inserted in the exhaust system that is designed to reduce noise

silencer (noun)	muffler (noun)
a tubular acoustic device inserted in the exhaust system that is designed to reduce noise	a scarf worn around the neck
short tube attached to the muzzle of a gun that deadens the sound of firing	a tubular acoustic device inserted in the exhaust system that is designed to reduce noise
	a device that decreases the amplitude of electronic, mechanical, acoustical, or aerodynamic oscillations