動物群裡排第一的公的
這一支就是核心畫面本身，沒有轉彎。
noun · B2
In a group of animals such as wolves or chimpanzees, the male that ranks above all the others. He usually eats first and the rest of the group moves aside for him.
（動物群中的）首領雄性
核心畫面
Picture a group of wolves or with one male sitting at the top of the order: he eats first, the others move aside, and his mood sets the mood of the group. Alpha is the first letter of the Greek alphabet, so the phrase names the male who comes first. Every later use is that same picture carried over to people.
可以想成一群狼或黑猩猩裡，有一隻公的排在最上面：牠先吃、別的成員讓路、牠的脾氣決定全場的氣氛。alpha 是希臘字母…更多收起
可以想成一群狼或黑猩猩裡，有一隻公的排在最上面：牠先吃、別的成員讓路、牠的脾氣決定全場的氣氛。alpha 是希臘字母的第一個，所以這個說法畫的就是「排第一的那隻公的」。之後的用法，都是把這張圖原封不動搬到人身上。From the word’s history
The phrase came out of scientific work on rank in social animals, and was later applied to men with dominating characteristics; it was already around in the 1990s and spread further after Neil Strauss's The Game (2005).
這個詞原本出現在研究動物社會階級的科學文獻裡，後來才被拿去形容具有支配性格的男人。1990 年代已經有人在用，2005 年 Neil Strauss 的 The Game 讓它流行起來。所以「動物首領」不只是比喻的說法，它真的是這個詞的出發點。
Wiktionary entry 'alpha male', etymology_text supplied in packet (source_ref kaikki:3f6f69a190036ae4:1089399427)
Two branches
搬到人身上：最強勢的那個男人
把動物群的那張圖蓋在一群人身上：誰講話大家會聽、誰的決定會過，誰就是那個 alpha male。因為人並沒有真的排序，這樣講就帶著誇張，所以英語用這個詞時多半是半開玩笑的。
noun · B2
A man that people treat as the most powerful and confident one in a group, the one the others follow. It is often said lightly, or as a joke about a man who acts this way.
團體裡最強勢的男人