Boyd’s Bible Dictionary:
(bearded). In N. T. sense one not a Greek (Acts 28:2; Rom. 1:14; 1 Cor. 14:11).
Concise Bible Dictionary:
The word signifies “foreigner, alien”; it was used by the Romans for any people who did not understand Latin or Greek. In Rom. 1:14 they are in contrast to the Greeks. In 1 Cor. 15:11, a person hearing another speak in a language he did not understand would account him and be accounted a foreigner. The inhabitants of Melita were so called by Luke. Acts 28:2-4. In Colossians 3:11 The “barbarian” is in contrast to the uncultivated Scythian.