舉起來給人看的一塊布
這一族就是核心畫面本身：一塊寬寬的布，掛在或舉在顯眼的地方。差別只在布上放什麼、布掛在哪裡。
noun · B2
A flag, especially the cloth that a king, a noble family, an army or a country is known by and that is carried or flown in front of its people.
旗幟
核心畫面
You can think of banner as one piece of cloth lifted on a pole where a crowd can see it. The cloth carries a mark: a colour, a family sign, a name, a sentence. Whoever stands under it is saying, without speaking, this is what I belong to. Almost everything else the word does keeps that shape — something wide and flat, put up in front of people, telling them which side you are on.
banner 可以想成一塊被高高舉起的布。布上有個記號：一種顏色、一個家徽、一個名字，或一句話。舉著它的人，等於不出…更多收起
banner 可以想成一塊被高高舉起的布。布上有個記號：一種顏色、一個家徽、一個名字，或一句話。舉著它的人，等於不出聲地說：我站在這一邊。後面幾乎所有的意思，都還留著這個畫面——一塊寬寬扁扁的東西，放在大家看得到的地方，告訴別人你屬於什麼、你要什麼。From the word’s history
Recorded as coming from Middle English baner, from Old French baniere, of Germanic origin, and the same source note links it to band. A band is something that ties people together, and a cloth on a pole is exactly the sign that a group is tied together — which is why the word later names the group as easily as the cloth.
資料記載 banner 來自中古英語 baner，再往前是古法語 baniere，源頭是日耳曼語，並註明與 band 同源。band 是把東西或人綁在一起的帶子。一塊布升在桿子上，正好就是「這群人綁在一起」的記號。所以這個字後來既可以指那塊布，也可以指旗下的那群人。
Wiktionary (kaikki extract, source_ref kaikki:3f6f69a190036ae4:630055029), banner etymology 1: From Middle English baner, from Old French baniere (Modern bannière), of Germanic origin. More at band.
Three branches
高舉起來的信念
布不見了，動作留下來。人還是「舉著」什麼站在前面，只是舉的變成一個主張、一個名字。
noun · C1
A belief, principle or cause that someone stands for openly and works for, spoken of as if it were written on a cloth they hold up for everyone to see.
旗幟（信念）
同一面旗底下的那群人
旗把名字借給了人。跟著同一面旗的隊伍，久了就直接被叫做那面旗；供養這支隊伍的土地也跟著叫旗，於是走進了地圖。
noun · C1
A body of soldiers who serve under one flag, and so also an official division of land and people organised that way — in the Qing empire, and today in Inner Mongolia and Tuva, a banner is a district of this kind.
旗（軍隊編制／行政區）