病從一個身體到另一個身體
這一族就是核心畫面本身：病菌進到裡面，並且往下一個對象移動。
infect (spread disease) · verb · C1
To pass a disease to another person, so that they become ill too.
傳染
核心畫面
One way to picture it: something invisible gets inside a body and does not stay there — it moves on to the next body, and the next. The picture is not just 'harm' but 'harm that spreads from one host to another'.
一個看不見的東西鑽進一個身體裡，而且不會待在原地：它從一個人跑到下一個人，再跑到下一個。infect 的重點不只是「…更多收起
一個看不見的東西鑽進一個身體裡，而且不會待在原地：它從一個人跑到下一個人，再跑到下一個。infect 的重點不只是「弄壞」，而是「弄壞的東西會自己傳下去」——所以同一個字後來可以用在食物和水（帶著病菌等著進到別人身體）、用在情緒（一個人的興奮讓整間房間都興奮起來）、也用在電腦（病毒鑽進磁碟，再傳給下一台）。From the word’s history
Latin inficiō meant 'to dip in, to dye, to taint' — the image of something soaking in and changing the colour of the whole, which is why the modern word is about a thing that gets inside and alters what it enters.
拉丁文 inficiō 原意是「浸染、染色、沾污」——把東西泡進染料裡，顏色就整個變了。這個染色的畫面正好解釋現代的核心：infect 說的不是從外面打壞，而是滲進去、把裡面整個改掉，而且沾到下一個東西時同樣會把它染上。
Wiktionary: infect (from Latin infectus, participle of inficiō 'dye, taint')
Two branches
會傳染的不只是病
把疾病的傳播方式整個借過來：情緒和程式碼都不靠推力擴散，而是接觸到就沾上、沾上就再傳。
infect (spread a feeling) · verb · C1
If a feeling or interest infects other people, it spreads to them and they start to feel or want the same thing.
感染
原始詞典資料6 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。
infectverb詞源 1/ɪnˈfɛkt/
- 1
To bring (the body or part of it) into contact with a substance that causes illness (a pathogen), so that the pathogen begins to act on the body; (of a pathogen) to come into contact with (a body or body part) and begin to act on it.
- Not everyone will be infected when an epidemic strikes.
- Bats host many high-profile viruses that can infect humans, including severe acute respiratory syndrome and Ebola.
- 2
To contaminate (an object or substance) with a pathogen.
- 3
To make somebody enthusiastic about one's own passion, or to communicate a feeling to others, or a feeling communicating itself to others.
- Her passion for dancing has infected me.
- Guido, by way of diverting the embarrassment which seemed to infect them all, began to unfasten the packet of letters.
- 4
computingengineeringmathematicsOf a computer virus: to insert its own code into (another executable file).
infectadj詞源 1/ɪnˈfɛkt/
- 1
obsoleteInfected.
- And in the imitation of these twain, / Who, as Ulysses says, opinion crowns / With an imperial voice, many are infect.
infectadj詞源 2/ˈɪnfɛkt/
- 1
raregrammarhuman-scienceslinguisticsRepresenting an action not yet completed.
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。