讓房間換氣的設備
這是最貼近字面的一支：要換氣的空間是房間、廚房或整棟樓。
noun · B2
A piece of equipment, often a fan or a covered opening in a wall or ceiling, that brings fresh air into a room or building and pushes the old, stale air out.
通風設備／換氣扇
核心畫面
A closed space with tired air inside it, and a machine whose only job is to swap that air: fresh air in, stale air out, again and again. The space may be a bathroom, an office, or a pair of lungs.
ventilator 的核心畫面可以想成一台「換氣的機器」。它的工作只有一件事：把新鮮空氣送進一個封閉的空間，再把裡…更多收起
ventilator 的核心畫面可以想成一台「換氣的機器」。它的工作只有一件事：把新鮮空氣送進一個封閉的空間，再把裡面悶住的空氣推出去，一進一出，反覆做。字的組成就寫著這件事：ventilate（使空氣流通）加上 -or（做這件事的東西）。所以看到這個字，先想「空氣進、空氣出」，再看它服務的是哪個空間。可能是一間浴室、一棟大樓，也可能是一個人的肺。兩種用法之間沒有轉彎，只是換了要換氣的對象。From the word’s history
From ventilate plus -or, the thing that ventilates; Latin already had ventilator.
由 ventilate（使空氣流通）加上 -or（做這件事的東西）組成；拉丁文裡本來就有 ventilator 這個字。
Wiktionary (kaikki extract, source_ref kaikki:3f6f69a190036ae4:861611045:27549): 'From ventilate + -or; cf. Latin ventilator.'
Two branches
讓肺換氣的機器
同一個動作換了對象：要換氣的空間從房間變成人的肺，機器代替胸腔一進一出。
noun · B2
A machine that pushes air into a person's lungs and lets it out again, used when someone is too ill or too weak to breathe well enough on their own.
呼吸器
原始詞典資料4 筆記錄
以下是外部詞典記錄的用法，原文照列，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。
ventilatornoun/ˈvɛntɪleɪtə/
- 1
A device that circulates fresh air and expels stale or noxious air.
- 2
medicinesciencesA machine that moves breathable air into and out of the lungs of a patient who is unable to breathe sufficiently.
- Near-synonym: respirator
- 3
Some behaviour or happening that relieves a tense atmosphere or situation.
- A lover's quarrel is made up of jealousies, doubts, hopes, fears, and all sorts of fantastic fancies: a matrimonial dispute, on the contrary, is composed of familiar and ordinary matter, a sort of ventilator to the temper!
- 4
obsoleteslangA play or an actor so bad as to empty the theater.
資料來源：英文維基詞典 English Wiktionary（CC BY-SA 4.0）。 原文照列，未經改寫。