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Dr. Shapiro's Puzzle of the Day

Today's Puzzle

Wednesday, May 26
Banana is a count noun: you can say "a banana", "three bananas", "too many bananas", and so on. Rice is a mass noun: you can say "a cup of rice", "three grains of rice", or "too much rice", but you can't say "a rice" or "three rices". (Well, you can, but people will give you a certain look.)

Sometimes mass nouns masquerade as count nouns. Peas were once pease, a mass noun like rice (as in "pease porridge hot, pease porridge cold"). It wasn't a plural, and there wasn't a singular form; when toddlers said "I eated a pea", their parents probably laughed at their double mistake. But over time, the obvious logic of peas/pea won out and a count noun was born.

But there's another common foodstuff which is still a mass noun today, despite looking like a plural. If you encounter this word without its final -s, it's almost certainly as an adjective (perhaps before milk or bread). What is it?

BONUS: Can you think of any other nouns that look like plurals but don't have singular forms?

   


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Yesterday's Puzzle + Solution

It had been my understanding that the early universe was too hot to sustain _________ hydrogen for the first half-billion years or so, and was therefore a necessarily opaque plasma of protons and electrons.

On October 11, some 60,000 _________ grocery workers at 852 stores in southern California went on strike or were locked out of their jobs.

That's a question we will all be debating this year when contract negotiations open between _________ nurses and the government.

Previous studies have shown that the _________ ammonia molecule and not the ammonium ion is the form of the toxicant harmful to fish.

These four sentences, taken from different webpages, illustrate some of the uses of a certain 9-letter word… or perhaps I should say multiple 9-letter words that happen to be spelled (but not pronounced) alike. To prevent confusion, a hyphen is sometimes added. What's the word?

Solution As Charlie wrote to me, how do you tell the difference between a plumber and a chemist? Ask them to pronounce "unionized".

(Kate adds: "now I am picturing righteously angry little hydrogen atoms marching around a picket line")

Congratulations to yesterday's solvers Carl, Charlie, Anna K., Yildiz, Jacob C., Atticus, Connor, Mrs. Gregg, Kate, Dr. Yetman, and Graham. Thanks to everybody who made a guess!

About This Site

Though he now teaches mathematics, Dr. (né Mr.) Shapiro's first job in a K–12 school was as a lunch monitor in Davis, CA. It was there that he originated the Puzzle of the Day, even rewarding correct answers with tickets in denominations like "15 points" (though without a clear idea of how he'd ultimately redeem these). Dr. Shapiro's favorite puzzle from this pre-professional era was "Tell me the location of the beehive on this campus."

Ten years later, Dr. Shapiro revived Puzzle of the Day at Proof School, writing each day's puzzle on a name tag. After 600 puzzles or so, he was just starting to feel normal about students reading his chest all the time when campus closed and the puzzle, like the rest of our lives, moved online. New puzzles are posted daily on school days.

Want to catch up on old PotDs? There's an archive currently containing puzzles from March 2020 to March 2021.