It can be a touch, sight, smell, or anything SO erotic that you get immediate quality wood. Also can cure extreme cases of the phenomenon known as a "bonershrinker".
Clinton: That maid just gave me a projectile boner, which you ALL know means that I gotta act on it. I hope my career won't be harmed.
by Reverend J. Izzy Commodde October 2, 2010
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