Acts 11:26 And when he had found him, he brought him unto Antioch. And it came to pass, that a whole year they assembled themselves with the church, and taught much people. And the disciples were called Christians (Christianos) first in Antioch.,P Acts 26:28 Then Agrippa said unto Paul, Almost thou persuadest me to be a Christian (Christianos).
Yet if any man suffer as a Christian (Christianos), let him not be ashamed; but let him glorify God on this behalf.
Christianos - follower of Christ
There is no word "Catholic" in the New Testament. Deal with it. It's a fact.
This is semantics. Do some research into the writings of the earliest Church Fathers ( Jurgens Faith of the Early Fathers) and the Didache, writings that predate the canonization of the New Testament. See what the earliest Christians believed, not what Martin Luther believed.
One doctrine you won't find in the early Church is Sola Scriptura. (You won't find it in the New Testament, either.)
"Listen to the Church." --Jesus
No word Trinity either. It is still a fact, deal with it.