Endocrinology

Entgleisen starts on the railway: der Zug ist entgleist, the train has come off the rails. English more or less stopped there, adding only the plan or the conversation that gets derailed. German took the word in two other directions, and both turn up on a ward. In medicine a value entgleist when the body’s own regulation lets go of it: der Blutzucker ist entgleist, and a discharge letter speaks of eine hypertensive Entgleisung or eine Stoffwechselentgleisung — not a slow drift but a sudden loss of control that has to be treated the same day. Among people, somebody entgleist who loses hold of tone or manners, and eine verbale Entgleisung is the remark that should never have been made. The three senses share an image rather than a subject: something that ran on rails and suddenly does not. Like its railway original the verb takes sein: der Wert ist entgleist, never hat.