Stand at a fair. In the middle is the big tent, and that is what everyone bought a ticket for. Along the edge is a row of small stalls: a ring to throw, a short act, a few coins each. They are loud, they are close to you, and they are easy to spend the whole evening on — and none of them is the reason you came. The word keeps both halves of that picture: at the side, and still a show.
sideshow 可以想成園遊會的場面。正中間是大帳篷，那才是大家買票來看的。場地邊上一整排小攤：丟個圈圈、看一段短表演，一次幾個銅板。它們很吵、離你很近，很容易讓你整晚都耗在那裡——但沒有一個是你來的理由。這個字一直保留著兩件事：位置在旁邊，而且它確實是一場秀。
From the word’s history
From side plus show: the show at the side, not the one in the middle.
來自 side（旁邊）加 show（表演），字面就是「旁邊的那場表演」。位置感是這個字的關鍵：它不在中央，卻很會搶眼睛。
Wiktionary entry for sideshow (packet evidence, source_ref kaikki:3f6f69a190036ae4:1147288702:12189): From side + show.
登入就可以看每一支怎麼連回核心畫面。