Nervous Pudding (jello)

“Nervous pudding” has been a popular nickname for Jell-O because it shakes when it’s handed off from the server. “‘Don’t get upset, Marge, calm your nerves with some of this nervous pudding,’ and Nell laughingly passed the gelatine” was cited in print in 1903.
 
   
Wikipedia: Jell-O
Jell-O is a registered trademark of Kraft Foods for varieties of gelatin desserts, including fruit gels, puddings and no-bake cream pies.
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In 1897, in LeRoy, New York, carpenter and cough syrup manufacturer, Pearle Bixby Wait trademarked a gelatin dessert, called Jell-O. He and his wife May added strawberry, raspberry, orange and lemon flavoring to granulated gelatin and sugar.[5] Then in 1899, Jell-O was sold to Orator Woodward, whose Genesee Pure Food Company produced the successful Grain-O health drink. Part of the legal agreement between Woodward and Wait dealt with the similar Jell-O name.
     
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May 1903, The Young Woman’s Journal, “The Lobbyists” by Marjorie Liske, pg. 227:
“Don’t get upset, Marge, calm your nerves with some of this nervous pudding,” and Nell laughingly passed the gelatine.
 
28 March 1909, Grand Forks (ND) Daily Herald, pg. 11, col. 5:
The menu was comprised of the following unique and appropriate dishes: Sweetheart sandwiches, moonshine, nervous pudding, miniature clubs, smarties.
 
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College Comedies
By Edwin Bateman Morris
Philadelphia, PA: The Penn Publishing Company
1911
Pg. 34:
COLLINS. So much so that they won’t be able to serve anything for the next year at his lunch-room but ice-cream and nervous pudding.
 
Chronicling America
22 February 1911, The Citizen (Honesdale, PA), pg. 8, col. 5:
The menu: Woman’s Grit, Fruit of the Tree, Spring Offering, Inhabitants of the Jungle, Nervous Pudding—the kind mother used to make.
 
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The Senior:
A College Comedy in Three Acts

By Edwin Bateman Morris
Philadelphia, PA: The Penn Publishing Company
1919  
Pg. 34:
COLLINS. So much so that they won’t be able to serve anything for the next year at his lunch-room but ice-cream and nervous pudding.
 
14 May 1920, Seattle (WA) Daily Times, “Bright Sayings of Children,” pg. 23, col. 2:
Carol, aged 5, was enjoying a dish of jello. Noticing it was rather wriggly she exclaimed: “My, but this is nervous pudding.”—F. M. F.
 
Chronicling America
2 January 1921, Richmond (VA) Times-Dispatch, “Angie Cornfield’s Christmas Dinner,” pg. 11, col. 4:
Dey called it jelatene, but de name I ggive it were nervous puddin’.
 
2 March 1936, Cleveland (OH) Plain Dealer, “Soda Jerkers Dish Up Fancy Idioms” (AP), pg. 8, col. 8:
Water may be designated as “city cocktail,” “city juice,” “dog soup,” “Hudson River ale,” “Potomac phosphate,” “Lake Michigan straight” or “tin roof,” and jelly may be descriptively termed “nervous pudding, “shimmering Liz” or “shimmy.”
 
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New York Panorama:
A Comprehensive View of the Metropolis, Presented in a Series of Articles Prepared by the Federal Writers’ Project of the Works Progress Administration in New York City

New York, NY: Random House
1938
Pg. 159:
In cafeteria, diners, lunchettes and luncheonettes the cries of countermen repeating orders to the chefs will prove amusing to the out-of-towner. Staples surviving the introduction of microphones include nervous pudding for Jello; burn the British or toasted Wally for a toasted English muffin; smear one, burn it for a toasted cheese sandwich; bottle o’ red for catsup; one to go for an order to be taken out; one cow for a glass of milk; stretch it for a large glass; burn one with a feather for a chocolate malted milk with an egg in it; and the strident eighty-six, a warning to the cashier that a customer is trying to leave without paying his check.
 
2 July 1943, San Francisco (CA) Chronicle, “Will Connolly Says,” pg. 1H, col. 7:
he staggers you with statistics like 70,000 stalks of asparagus at one sitting, tons of potatoes, millions of slices of bread and tanks of nervous pudding, which he interprets as Pearl Harbor for gelatin.
 
10 August 1950, Evansville (IN) Courier, “Broadway” by Jack Lait, pg. 10, col. 3:
More counterman slang:
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“Nervous pudding—Jello.
 
18 April 1979, Washington (DC) Star, pg. D-10, col. 1:
Dinering out: These terms are used in American diners: “Adam and Eve on a raft” (poached eggs on toast), “clean up in the kitchen” (hash), “nervous pudding” (Jell-O).
   
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Cassell’s Dictionary of Slang
By Jonathon Green
London: Weidenfeld & Nicolson
2005
Pg. 996:
nervous pudding n. (also nervous salad) [1930s-40s] (US) a dish made with gelatine or aspic, [it shakes]
 
Unravel Magazine 
The Delicious Guide to Diner Lingo
by Daniel Adler on September 1, 2015
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Nervous Pudding Jello