Picture civilized as people who have agreed how to live together: small agreements about how you treat the person next to you, and large ones like law, government and schools. Uncivilized is the un- of that picture — standing outside the agreement. Zoom the camera in and it is one person ignoring the rules of the room. Zoom it out and it is a whole society described, from outside, as having none of those systems at all.
Wiktionary gives the word as un- + civilized, so it is built as the plain negative of the civilized picture; the prefix adds nothing else.
Wiktionary 記的來源就是 un- + civilized。所以這個字是 civilized 的直接反面，前綴沒有另外加進別的意思。
Wiktionary entry 'uncivilized' (packet source_ref kaikki:3f6f69a190036ae4:745653973): 'From un- + civilized.'
Two branches
行為：不照大家講好的規矩來
這是鏡頭拉近的那一半。約定不是抽象的東西，它就落在圖書館要安靜、碗盤自己洗、隊伍要排這些小事上。有人不照做的時候，就是站到了約定外面。
adjective · B2
Behaving in a rude, unpleasant way that breaks the basic rules people follow when they share a space, so that most people around would call it unacceptable.
沒教養的；不文明的
社會：舊書裡的「未開化」
這是鏡頭拉遠的那一半。同樣是「在約定外面」，只是約定變成了法律、政府、貨幣這些制度，被放到外面的也從一個人變成一整個社會。
adjective · C1
Used about a group of people or a society to say that they live in a very simple way and have not built up systems such as laws, government, money or schools.
未開化的