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1.
From the 'National Lampoon's Christmas Vacation' movie character, Clark Griswold and his overdone Christmas lights display.

Any obscenely over-the-top holiday lights display on someone's home. Often done in an insanely competitive, anti- "peace on Earth, goodwill towards men" desire to outdo and one-up the neighbors.
Jack: Dude, you're late for work again. And you've been looking like hell lately. What's up?

Shawn: I haven't had any sleep in days. My neighbor's Griswoldian Christmas display is so freakin' bright it's been keeping me up all night. AND it's draining so much power it caused a black out in my neighborhood last night, so my alarm clock didn't go off!
by Wasabi-Woman December 07, 2009