1) the extreme level of not giving a fuck that prolonged exposure to tropical island paradise can cause.

2) a temporary transition to "island time" or a slowing down of thought process caused by prolonged exposure to tropical island paradise.
guy 1: "hey can you help me with the math project?"

guy 2: "sorry bro, i got the island brain goin on"
by longjohnawesome April 26, 2011
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Slang for a powerful street drug. It is a razor sharp crystalline chemical that you tuck under your eyelid. When it cuts your eyeball open it slips into your blood stream and directly into your brain. The high is terryfing. It takes all your greatest fears and insecurities and gives them teeth and arms, and then it locks you in a room with them from which you cannot escape. There is also a surprise at the end of the high.
You realize the face of god is somewhere inside your body, but you can't find it.. and it hates you.

Just when you can't take anymore.. you poop your mouth.

Long island brain slice is also known as god drug, cuddy cuddy, elmo, cat vaj, and funt.
by Bourbon & Apple Cider Vinegar October 30, 2014
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