A line that runs along the bottom of something. It never gets in the way of the words above it — it just sits underneath and holds them up, and because it sits there, your eye goes to whatever is resting on it. Draw it under a word and the word matters more; leave it alone on a keyboard and it becomes a character you can type; put music in that same low position and it carries a scene without being noticed.
From the word’s history
The packet gives the compound only: under- + score. Score names a scratched or drawn mark, so the word reads as a mark made underneath.
本包裹的字源只說它由 under- 加 score 組成。score 指的是劃出來或刻出來的痕跡，所以整個字讀起來就是「在下面劃的一道痕」。
Wiktionary entries ‘underscore’ (noun source_ref kaikki:3f6f69a190036ae4:916556863:15281; verb source_ref kaikki:3f6f69a190036ae4:916572144:10758): etymology_text ‘From under- + score.’
登入就可以看每一支怎麼連回核心畫面。