A fork of Rural Dictionary
A marriage between first-cousins. The marriage is considered a "horseshoe" marriage due to the marriage's connection in a marriage resembling a horseshoe on a family tree (the daughter of one side connects to the parents of the son of his parents as the parents have blood-sibling relations.
"Hey Dave, did you hear that Bryan's marrying Rachel?" "Yeah man, it's a horseshoe marriage though so they might have to get married in another state." "Damn man, incest..."