What is "collar-and-elbow"

Collar-and-elbow wrestling is a style of folk wrestling native to Ireland that can be traced back to the 17th century but it has ties to the Games of Tailtinn between 632 BC and 1169 AD. Though originating in Ireland, the style flourished in America. Collar-and-elbow features an array of trips, mares/throws, hip-locking, shin kicking, pinning combinations, and submissions.