1 definition by cheeseplaydoh

1: Someone who ruins someone else's fun.

2: A fan of the progressive 90's Canadian punk band, The Killjoys.
1: Max took the band out, and Conan the killjoy got peeved, and screamed at them. The party was ruined.

2: "Today I Hate Everyone" is Kev's favorite song, he's a total killjoy
by cheeseplaydoh August 11, 2004
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