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2.
A medical condition in which the sufferer takes on the traits of muppet: being silly. Muppetitis very contagious.
Hind has muppetitis.
by TheMuppets October 28, 2009
 
1.
Someone who regularly behaves like a muppet.
i.e. you have a severe case of muppetitis
by Suni January 23, 2005