飛機在天上纏
飛行員把那團扭打的畫面搬到天上：距離近到看得見對方，兩架飛機一直繞、一直轉，各自想咬住對方的尾巴。這是一個比喻的連結，不是說飛機的用法從狗的用法「演變」出來的歷史證據。今天的學習者其實更常先遇到這一支。
noun · B2
A fight in the air between two or more military planes, in which the pilots turn and twist around each other at close range.
空中纏鬥
核心畫面
Think of two dogs that have got hold of each other and will not let go: they spin, snap, and keep circling, each one trying to get behind the other. Everything this word covers is that one tangled, close-up scrap — even when the fighters are made of metal and are a thousand metres up.
可以想成兩隻狗咬住對方不放：牠們一直轉、一直換位置，誰都想繞到對方後面去。整個畫面的重點是「近」和「纏」，不是誰站在…更多收起
可以想成兩隻狗咬住對方不放：牠們一直轉、一直換位置，誰都想繞到對方後面去。整個畫面的重點是「近」和「纏」，不是誰站在遠方出手。這個字所有的用法，都可以想成同一團扭打——只是後來打架的變成了金屬做的、飛在一千公尺高的東西。From the word’s history
The word is simply dog + fight, so the animal picture is right there in its two halves.
這個字就是 dog（狗）加 fight（打架）兩個字拼起來，所以那個扭打的畫面本來就寫在字面上。飛機的用法是後來借過去的比喻，不是另一個來源。
Wiktionary entry for dogfight (kaikki:3f6f69a190036ae4:1269469125): From dog + fight.
From the picture
Also in this word
noun · B2
A fight between dogs that people have arranged and come to watch, treated as a sport by those who organise it.
鬥狗（人為安排的狗打鬥）