Yet another slang term for erection. When the man-meat is as hard as the tool used by a diamond miner to cut through rocks.
Dude 1: "Did you see the ass on that chick? Huh, huh? I was hard as a diamond miner's pick axe!"
Dude 2: "Way to go, Dawg!"
Dude 2: "Way to go, Dawg!"
by Wizards Sleeve October 1, 2006