1 definition by John J. Smith

1)Someone that ruins a hilarious joke by taking it too far
2)Someone that ruins a moment by telling a terrible joke
3)Someone that laughs really hard at a totally not funny joke
Everyone is having a great time telling jokes and then some guy tells a chicken crosses the road joke that ends with the chicken crossing the road to get to the other side. This person is a joke killer.
by John J. Smith December 20, 2007
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