Acts 11:26  . . . The disciples were first called Christians in Antioch.

Here are just a few Scriptures showing how disciple was the common name for a believer:

Acts 6:7 The word of God increased and the number of the disciples greatly multiplied in Jerusalem. A great company of the priests were obedient to the faith.

Acts 9:1-2 But Saul, still breathing threats and slaughter against the disciples of the Lord, went to the high priest and asked for letters from him to the synagogues of Damascus . . .

Acts 9:26 When Saul had come to Jerusalem, he tried to join himself to the disciples; but they were all afraid of him, not believing that he was a disciple.

Acts 14:21-22 When they had preached the Good News to that city, and had made many disciples, they returned to Lystra, Iconium, and Antioch, strengthening the souls of the disciples, exhorting them to continue in the faith . . .

Acts 15:10 Now therefore why do you tempt God, that you should put a yoke on the neck of the disciples which neither our fathers nor we were able to bear?

Acts 18:23 Having spent some time there, he departed, and went through the region of Galatia, and Phrygia, in order, establishing all the disciples.

The Interpreter’s Dictionary of the Bible, edited by George A Buttrick et al, Abingdon Press (Vol 1, page 845) points out that in Acts, ‘disciple’ is “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’ . . .”