percussion

Short definition from Wiktionary

Noun

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