\Per*cus"sion\, n. [L. percussio: cf. F. percussion.
See {Percuss}.]
1. The act of percussing, or striking one body against
   another; forcible collision, esp. such as gives a sound or
   report. --Sir I. Newton.
2. Hence: The effect of violent collision; vibratory shock;
   impression of sound on the ear.
         The thunderlike percussion of thy sounds. --Shak.
3. (Med.) The act of tapping or striking the surface of the
   body in order to learn the condition of the parts beneath
   by the sound emitted or the sensation imparted to the
   fingers. Percussion is said to be immediate if the blow is
   directly upon the body; if some interventing substance, as
   a pleximeter, is, used, it is called mediate.
{Center of percussion}. See under {Center}.
{Percussion bullet}, a bullet containing a substance which is
   exploded by percussion; an explosive bullet.
{Percussion cap}, a small copper cap or cup, containing
   fulminating powder, and used with a percussion lock to
   explode gunpowder.
{Percussion fuze}. See under {Fuze}.
{Percussion lock}, the lock of a gun that is fired by
   percussion upon fulminating powder.
{Percussion match}, a match which ignites by percussion.
{Percussion powder}, powder so composed as to ignite by
   slight percussion; fulminating powder.
{Percussion sieve}, {Percussion table}, a machine for sorting
   ores by agitation in running water.