The Twelve Apostles were just some of Jesus many disciples:
Before the name Christian was even coined, all true Christians were called disciples:
(None of the twelve apostles were in Antioch.)
The Interpreters Dictionary of the Bible, edited by George A Buttrick et al, Abingdon Press (Vol 1, page 845) says that in the Gospels and Acts disciple is:
Of over 230 instances of the term in the gospels, about 90 per cent either are not limited to the Twelve at all, or else do not make clear whether these or some other larger group is indicated.
Luke 6:13 When morning came, he called his disciples to him and chose twelve of them, whom he also designated apostles
Acts 11:26 . . . The disciples were called Christians first at Antioch.
the most frequent and general term for believers in Christ. The word is used twenty-two times in Acts, as compared with four instances of saint, two of Christian, and one of Nazarene . . .