Picture a sign in a hospital corridor that reads OLD AGE, with an arrow pointing down the ward. Geriatric is that sign stuck onto something: onto a ward, a clinic, a nursing course, a research budget. Every serious use of the word is the sign doing its job. The joking uses are the sign being carried out of the hospital and stuck on other things — an ancient printer, a band still touring at seventy, and sometimes on a person, as a name. The hospital smell never comes off it, which is why it lands hard on people: it says you belong down that corridor now.
Formed from geriatrics: Ancient Greek gêras (old age) plus -iatric (to do with medical treatment). The medical frame is in the word from the start, not added later.
這個字是從 geriatrics 來的：希臘文 γῆρας（gêras，老年）加上 -iatric（跟醫療有關）。醫療的框架從一開始就在字裡面，不是後來才加上去的。
Wiktionary entry for geriatric, etymology_text supplied in the evidence packet (kaikki:3f6f69a190036ae4:1333231868)
From the picture
把醫院的牌子貼到別的東西上
同一塊牌子被搬離醫院。貼在機器或人身上，等於說「這已經該送去老年科了」，笑點和刺人的地方都在這裡。
adjective · C1
Informal: so old that it no longer works well — slow, worn out or out of date. It is said about machines and equipment, and about people or groups that seem past their best.
老掉牙的／老得不中用
adjective · B2
Used before a noun for the medical care of old people — the doctors, nurses, wards, clinics, training and services that look after them, and more widely for health matters that belong to old age.
老年醫療的／老人照護的
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。
geriatricadj/ˌdʒɛɹ.iˈæt.ɹɪk/
Relating to the elderly.
Elderly, old.
Relating to geriatrics.
geriatricnoun/ˌdʒɛɹ.iˈæt.ɹɪk/
slangAn old person.
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。