You can think of barbarous as a word spoken from inside a circle about someone standing outside it. The circle is whatever the speaker counts as civilized: their laws, their learning, their language, their manners. Anything beyond the line gets this word, and the word carries the speaker's low opinion with it. So it stretches in three directions: people outside the circle are called uncivilized, acts that the circle finds shocking are called cruel, and writing that breaks the circle's rules is called impure. The line, not the people, is what the word is really describing.
From the word’s history
Wiktionary gives the route as Late Middle English, from Latin barbarus meaning foreigner or savage, from Ancient Greek barbaros meaning foreign or strange. The oldest picture is simply someone whose speech you cannot follow, and that is why the same word can end up meaning uncivilized, cruel, and, of language, impure.
依 Wiktionary，這個字來自晚期中古英語，源頭是拉丁文 barbarus（外地人、野蠻人），再往上是古希臘文 bárbaros（外來的、陌生的）。最早的畫面只是「講話我聽不懂的人」。從這個起點往外走，就能理解它為什麼同時能表示未開化、殘暴，以及語言不純正這三件事。
Wiktionary entry for barbarous, etymology_text supplied in this packet (source_ref kaikki:3f6f69a190036ae4:959333978:10029)
登入就可以看每一支怎麼連回核心畫面。