Q: I have a question that you might want to run on New Year’s Eve. (I won’t be in any condition to read your answer on New Year’s Day.) Why does the expression “hair of the dog” refer to treating a hangover with more of the same?
A: The expression for an alcoholic drink taken to cure a hangover is a shortening of “a hair of the dog that bit you,” according to the Oxford Dictionary of Word Origins (2nd ed.), by Julia Cresswell.
Cresswell writes that the expression is derived “from an old belief that someone bitten by a rabid dog could be cured of rabies by taking a potion containing some of the dog’s hair.”
When the expression is used to mean a hangover cure, she explains, it “suggests that, although alcohol may be to blame for the hangover (as the dog is for the attack), a smaller portion of the same will, paradoxically, act as a cure.”
“There is, it should be added, no scientific evidence that the cure for either a hangover or rabies actually works,” she writes.
As far as we can tell, the idea that a potion made from a rabid dog’s hair could cure rabies originated in classical antiquity. The earliest example we’ve found is in the writings of the first-century Roman philosopher Pliny the Elder.
In Naturalis Historia, he writes: “When a person has been bitten by a mad dog, he may be preserved from hydrophobia by applying the ashes of a dog’s head to the wound.” Pliny adds that one could also “insert in the wound ashes of hairs from the tail of the dog that inflicted the bite.”
(From book 29, chapter 32, “Remedies for the Bite of the Mad Dog,” in an 1855 translation by John Bostock and H. T. Riley in the Perseus Digital Library at Tufts University.)
Although the belief that a rabid dog’s hair could cure rabies originated in classical times, the English expression “a hair of the dog that bit one” didn’t show up in writing until the 16th century. And from the beginning it was used figuratively to mean a hangover remedy.
The earliest example in the Oxford English Dictionary is from A Dialogue Conteinyng the Nomber in Effect of All the Prouerbes in the Englishe Tongue (1546), by John Heywood:
“I praie the leat me and my felowe haue / A heare of the dog that bote vs last nyght” (“I pray thee let me and my fellow have / A hair of the dog that bit us last night”).
The only OED citation for the expression used literally for a rabies treatment appeared in the 18th century: “The hair of the dog that gave the wound is advised as an application to the part injured.” (From A Treatise on Canine Madness, 1760, by Robert James.)
The dictionary’s first example for the short version of the expression is from a caption in the Jan. 5, 1935, issue of the New Yorker: “Your hair of the dog, sir.”
However, we’ve found many earlier examples, including this one from the Oct. 5, 1853, issue of the Wabash Express (Terre Haute, Ind.), about a man with “talent and genius of a high order” who “has thrown them all away to gratify his inordinate thirst for strong drink”:
“Prof. K., mistaking the character of the house we kept, called at our sanctum on Monday and asked for ‘a little bitters.’ We told him we did not keep the article, and as he was very full, advised him against taking any more. He said he had been sick, and that ‘the hair of the dog would not do him any further harm.’ ”
We’ll end with a nonalcoholic hangover concoction found in “Jeeves Takes Charge,” a P. G. Wodehouse story published in the Saturday Evening Post, Nov. 18, 1916. Here’s a description of the brainy valet’s first encounter with Bertie Wooster, who’s feeling the aftereffects of “a rather cheery little supper with a few of the lads”:
“I was sent by the agency, sir,” he said. “I was given to understand that you required a valet.”
I’d have preferred an undertaker; but I told him to stagger in, and he floated noiselessly through the doorway like a healing zephyr. … He had a grave, sympathetic face as if he, too, knew what it was to sup with the lads; and there was a look in his eyes, as we stood there giving each other the mutual north-to-south, that seemed to say: “Courage, Cuthbert! Chump though you be, have no fear; for I will look after you!”
“Excuse me, sir,” he said gently.
Then he seemed to flicker and wasn’t there any longer. I heard him moving about in the kitchen, and presently he came back with a glass in his hand.
“If you would drink this, sir,” he said with a kind of bedside manner, rather like the royal doctor shooting the bracer into the sick prince. “It is a little preparation of my own invention. It is the dark meat-sauce that gives it its color. The raw egg makes it nutritious. The red pepper gives it its bite. Gentlemen have told me they have found it extremely invigorating after a late evening.”
I would have clutched at anything that looked like a life line that morning. I swallowed the stuff. For a moment I felt as if somebody had touched off a bomb inside the old bean and was strolling down my throat with a lighted torch, and then everything seemed suddenly to get all right. The sun shone in through the window; birds twittered in the tree tops; and, generally speaking, hope dawned once more.
“You’re engaged!” I said as soon as I could say anything.