barbarian

1. A non-Greek or a non-Roman citizen.
2. An uncivilized or uncultured person, originally compared to the hellenistic Greco-Roman civilisation; usually associated with senseless violence and self-harm or other such shows of brute force and lack of mental faculty.
3. A person destitute of culture; a Philistine.
4. Someone from a developing country or backward culture.
5. A brutish warrior depicted in sword and sorcery and other fantasy works; typically clad in primitive furs or leather and usually favoring physical strength over intelligence while often possessing a bellicose temperament and disdain for laws.
6. A cruel, savage, inhumane, brutal, violently aggressive person, particularly one who is unintelligent or dim-witted; one without pity or empathy.
7. A foreigner, especially with barbaric qualities as in the above definitions.

Plural barbarians