A veritable mane of unruly pubic hair, often, nay, always accompanied by a massive overgrowth of ferocious facial hair. May be inhabited by various species of wildlife including: crabs, sabertooth crotch crickets, lice, fleas, small feral cats and the mythical crabacus. The downstairs beard, if left unchecked, will grow together with the upstairs beard creating one mammoth superbeard which will then slowly begin to digest it's host creature and become a sentient being.
Dude 1: "Dude! Why do you keep scratching your nuts? Knock it off!"
Dude 2: "Sorry, I've got something crawling around in my downstairs beard!"
Dude 2: "Sorry, I've got something crawling around in my downstairs beard!"
by Kipper snack rodeo June 12, 2009