percussor

/pərˈkʌsər/
noun
  1. A person or thing that strikes or hits something, especially a medical instrument used to tap the body to examine internal organs.
    • The percussionist acted as the main percussor during the performance.
    • The doctor used a percussor to check the patient's lungs.
    • In the band, the percussor kept the rhythm steady on the snare drum.