Alma 2:11

Now the people of Amlici were distinguished by the name of Amlici, being called Amlicites; and the remainder were called Nephites, or the people of God;

Amlici’s people were called Amlicites. Everyone else was called Nephites or God’s people.

Amlici’s followers became known as Amlicites. The rest were called Nephites, or the people of God.