Nackenklatscher
A Nackenklatscher is like a slap on the neck so hard it feels like you got hit with a wooden spoon and a curse.
My brother gave me a Nackenklatscher so hard I fell over like a sack of potatoes.
My mom gave me a Nackenklatscher for eating the last slice of pizza.
My friend gave me a Nackenklatscher because I called his dog a bad name.