The act of farting in the shower as water muffles the noise causing it to sound somewhat like Donald Duck laughing.
I took a shower earlier and farted, sounded like Donald duck laughing, a total Shower Quack
by StolenDignity February 10, 2012
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When a fart is conducted in the shower and the water running over the anus makes it sound like a duck quacking.
Friend 1: "I farted in the shower earlier and it sounded like Donald Duck laughing."

Friend 2: "SHOWER QUACK!"
by Unwept, the Lone Magpie February 10, 2012
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