six pack
n.— «The U.S. Coast Guard has much to do today with Homeland Security and policing matters, so they are asking the auxiliaries to expand their inspections to include Uninspected Passenger Vessels, commonly called six packs (six passenger vessels run by the charter captains and commercial fishing vessels).» —“Adriaan terMeulen’s goal is boating safer every day ” by Carl Kelly Marco Island Sun Times (Florida) July 27, 2006. (source: Double-Tongued Dictionary)