Two-Boater
A stupid person, originally from Ireland now living in Boston. A Two-Boater is an Irishman who set sail for Boston but landed in Nova Scotia (or Newfoundland) and it took 10 years to realize the error, thus requiring a second boat trip to reach the final destination. In Boston hierarchy, there are "Lace Curtain" Irish (rich), "Shanty" Irish (working class), and "Two-Boaters" (morons, idiots, etc.).
"Your brother is an idiot - he must have some Two-Boater in him"