The word “Christian” comes from the Greek word “christianos”, meaning “little Christ”. In fact, the Bible says in Acts 11:36:
“(…) So it was that for a whole year they assembled with the church and taught a great many people. And the disciples were first called Christians in Antioch.”
They were called Christians because they believed in Jesus Christ AND because they chose to go after the mission that was given to them (and to us): to represent Christ and make Him known!