Apostle -Galatians 1

Gal 1:1 Paul, an apostle(not sent from men nor through the agency of man, but through Jesus Christ and God the Father, who raised Him from the dead)
This gives a definition to what a true apostle is: not ordained by a church or ministers; not recognised by certain people, not trained by men or other leaders, not welcomed or accepted by audience, but simply called and sent by God.