What is Brainwave?
1.
British slang for a sudden, clever idea. Similar to the American "brainstorm." Often used sarcastically.
Suzie invited the neighbors in to see her most recent brainwave, a water fountain in the middle of her living room.
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2.
When you are receiving oral pleasure (fellatio) and when you are about to blow your wad, you cum in her nose which feels like when you dive in a pool incorrectly and all that water gets into your sinuses and hurts, thus the name brainwave.
Dude, I was getting blown by Jessica and i just felt like giving her a brainwave, she passed out, then I gave her another one.
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