The nickname given to the male reproductive organs of people named Brian, although most Brians do not qualify. It is infact not a raft at all, but is rideable and my be wet and rough at times. Riding the B-Raft is often referred to as "white water rafting."
"Im going white water rafting on the B-Raft! You can't come though, it has a one man capacity."
by HopperChopper March 10, 2009