To define something in its simplest terms after something is explained in a complex form, making the simple person look like a dumbass since everyone understood it the first time.

Origin - Gilligan from Gilligan's Island. He always did this when the Professor explained why something did or did not work
Classic Gilliganism:

Professor: "In order to make this new coconut-based radio function properly, we need an new receiving antenna installed on top of that coconut tree by the lagoon. In order to properly support it, someone will have to be ambidextrous."

Gilligan: "Yeah, and they have to use both hands,too."
by Dr. Freeze July 4, 2009
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A person that lacks any skill or knowledge in regards to boating.
These gilligans ran aground the other day and I had to tow them off the sandbar.
by Gtrain April 10, 2007
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1)to spend time with beautiful women coming on to you with no possible consequences (it was the sixties), and yet avoid getting laid for seven years. I mean, WTF?
I'm pretty sure Herman Munster or Eddie Haskell wouldn't have pulled a Gilligan if they had their druthers.
by Pantaloon January 28, 2008
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v. to sabotage

n. saboteur

n. monkey wrench

n. conspiracy of one
ex. We are not getting off this island because there is a gilligan on it.

ex. The boat motor died because it had been gilliganed.

ex. Everything was working accordingly until Mary Anne threw a gilligan into the situation.
by theropingeffect January 6, 2010
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A person or persons who have been marooned on a deserted island but find themselves in a pleasant situation.
Omg Did You Hear About Those People On The Island?

Yah I Heard They Were Gilliganed.
by klosekilla August 7, 2008
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a stupid, often clumbsy and dimwitted individual. makes random noises such as MARGH! but are not as dumb as they seem
Gilligan farted in assembly again, then laughed when people said he shat himself
by dude November 3, 2003
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A person that is part of the television show, "Gilligan's Island". The whole story line has to do with them going on a trip on a boat, and then a storm come and they get casted away, and they land on a desserted island that isnt on any map. They had like 100 chances to get out of the island but one person always messes the plan up, guess who? Gilligan. I don't get why they dont just kill him he's the one that gets them stuck on the island and messes up their plan to get off it.
by monkeymofo April 21, 2004
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