A delegation is a group of people who act as representatives of a larger group. If you’re a member of Congress from the Sunshine State, you’re a member of the Florida delegation.
Ever seen the opening ceremonies of the Olympic Games? Each country's delegation enters the stadium as a group, marching behind its own flag. Some delegations are a few hundred people, some are only a few, but each delegation is made up of the athletes and coaches sent to represent their country. You can also use delegation to mean assigning something to someone. While you're in the Amazon, you'll need to arrange with your roommates for delegation of your bill-paying duties.