Dual pair

Imagine you have two best friends, and they also have two best friends each. That means you have a total of four people who are your best friends' best friends. This is called a dual pair, where two groups of friends have a connection to each other through their mutual friendships. The term "dual" means two, and "pair" means a group of two, so a dual pair is two groups of two that are connected to each other. It's like a big circle of friends where everyone knows everyone else.