You can picture affront as something that comes straight at a person's face. Not a push from behind, and not a quiet remark they hear about weeks later. It arrives in front of them, in the open, where they and everybody else can see it land. That is why the word always carries the feeling of being made small in public rather than simply being upset. The verb is the throwing; the noun is the thing thrown. Same picture, two jobs.
The supplied source traces affront to Old French afronter, to hit in the face, from Latin ad, to, plus frons, forehead. The modern word keeps that front-facing picture: what makes an affront an affront is that it is done openly, to the person's face.
packet 附的來源把 affront 追到古法文 afronter（打在臉上），再往前是拉丁文 ad（朝向）加 frons（額頭）。今天的用法還留著那個正面的畫面：affront 之所以是 affront，就在於它是當面做出來的。
Wiktionary entry for 'affront' as supplied in this packet (source_ref kaikki:3f6f69a190036ae4:737581695): 'from Old French afronter (to hit in the face; to defy), from Latin ad + frons (forehead)'.
One branch
當著面讓人難堪
兩個意思都站在同一個畫面上：東西正面落在人臉上。差別只在你看的是動作還是那個東西。
verb · C1
To insult someone openly, especially by treating them as if they do not deserve respect. It is most often used in the passive: if you are affronted by something, it makes you feel insulted.
冒犯；侮辱