1. What a helmet is for.

2. A quasi-marijuana saying which is code for "Kush in your brain", or smoking the reefer. Used in situations where you can't openly proclaim your love for god's plant, so you simply say cushion your brain!
1. Dude1: Aw man, i nailed my head on my car door!
Dude2: Damn dude, sounds like you should've cushioned your brain.

2. Dude 1: Hey man last night was fuckin' crazy!
Dude 2: Yeah dude you had a shitload of Cushion your brain!
by Kush-in your BRAIN! June 25, 2009
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