\Si"lenc*er\, n.
One that silences; specif.:
(a) The muffler of an internal-combustion engine.
(b) Any of various devices to silence the humming noise of
    telegraph wires.
(c) A device for silencing the report of a firearm shooting
    its projectiles singly, as a tubular attachment for the
    muzzle having circular plates that permit the passage of
    the projectile but impart a rotary motion to, and thus
    retard, the exploding gases.