Savage, Uncivilized, Uncivilised
noun, な adjective
Barbarians who live in fields, not even in huts or houses or anything, are called savage by people who DO live in huts and houses. They think if you live out in a field you're really uncivilized. But that's all a matter of opinion, I guess.
やばん
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
そんな野蛮な人たちと付き合ってはいけません。
You must not associate with such savage people.