A retinue is an entourage, a crew, a posse. It's the group of people that accompany an important person.
Retinue shares a root with retain. This fact can help you remember the word. If you hire someone to help you out while you travel, you are retaining their services. When their services are retained, they become part of your retinue. Another example: A celebrity's retinue might include a hair dresser, a personal assistant, and a toy poodle.
