Christaelphians (from the Greek for Brothers of Christ / Christ's Brethren: Christou Adelphoi; cf. Greek of Colossians 1:2 - "brethren in Christ") are a Christian group that developed in the United Kingdom and North America in the 19th century. The name was coined by John Thomas, who was the group's founder. There are an estimated 50,000 Christadelphians in 120 countries.