Origin of Slapstick from Wikipedia:
The phrase comes from the batacchio or bataccio; called the
"slap stick" in English — a club-like
object composed of two wooden slats used in Commedia dell'arte.
When struck, the battacchio produces a loud smacking noise, though
little force is transferred from the object to the person being
struck. Actors may thus hit one another repeatedly with great
audible effect while causing very little actual physical damage. It
was among the earliest special effects. Don't forget to bring a
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