percussion

noun7

1. •
   The collision of two bodies in order to produce a sound.
2. •
   The section of an orchestra or band containing percussion instruments; such instruments considered as a group; in bands, may be separate from drum kits.
3. •
   The tapping of the body as an aid to medical diagnosis.
4. •
   The repeated striking of an object to break or shape it, as in percussion drilling.
5. •
   The sound so produced.
6. •
   The detonation of a percussion cap in a firearm.
7. •
   The outer side of the hand.