A more thorough explanation:

A priority award is a final decision made by the U.S. Patent and Trademark Office that determines which party in an interference contest was the first inventor. This award is also known as an award in interference.

For example, if two inventors file for a patent on the same invention, an interference contest may arise. The U.S. Patent and Trademark Office will then determine which inventor was the first to come up with the invention and award them the priority award.

This award is important because it determines who has the right to the patent and can prevent legal disputes between inventors.