To brain (flip out a testicle) on a train platform as your friends are leaving on a train) or just waiting...)

Look up braining for more explicit definitions but you get the idea. It looks like a little brain.
My friend brained us to say goodnight after a great day at the beach. It was difficult to see and blurry so we uploaded it to FB, just to basically say don't do that Within 20 seconds he messaged us that his brain was already visible in Malaysia so of course we deleted it. Hilarious though. Apparently it is a traditional goodbye in South Park, Colorado. Most guys do it. He just didn't expect my gf to take a photo or for it to go viral in 20 seconds. The Colorado Farewell. Then they slide down a mountain with no skis or helmet backwards with a bag of gummies. Braining the whole way.
by TheOtherScientist June 10, 2023
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