boners that seem to come from nowhere, and for no reason. Can tend to be embarassing, and can often lead to extremely humorous moments.
One guy: Dude ive been getting alot of mystery wood lately.
Other guy: What the fuck is mystery wood?
Guy grabing a hold of his boner: THIS!
Other guy:WHAT THE FUCK MAN!
Guy with boner: Exactly theres no reason for this, why did it show up, well never know.