a hand gesture where the thumb and middle finger are perpendicular to each other and the pointer/index is evenly in between. (other fingers are not seen)

meaning: peace,live on the edge,be X-treme, and wish me luck
person says "dude im gonna do this insane jump." (guy shows the 45-90 sign) and says "sweet thats gonna be awesome i gotta try"
by BrassBoi April 19, 2008
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