WASHINGTON (Reuters) - At the annual Scripps National Spelling Bee this week, hundreds of youngsters will compete in a uniquely American contest that has been likened to an intellectual extreme sport, involving one of the world’s most tricky languages.

Robert Foster of Kensington, Maryland, reacts after correctly spelling a word during the Scripps National Spelling Bee at National Harbor in Maryland, U.S. May 29, 2018. REUTERS/Kevin Lamarque

The competitors, some as young as 8 years old, face a three-day obstacle course through the English language, a mash-up of Germanic and French words laced with borrowings from tongues around the world. Any of 470,000 entries in the “Merriam-Webster Unabridged Dictionary” is fair game.

Their challenge is to outlast the field by coming up with the correct spelling of obscure words that often feature any one of a number of letter combinations that form identical sounds in English.

For the grade-school students who have trained year-round for the event, the pressure is enormous. They will compete for a $40,000 top prize, under the bright lights of ESPN, the cable channel that covers the competition as if it were tennis or skate-boarding.

“When I was competing it was an absolute pressure cooker, but not to the extent it is today,” said Nupur Lala, 33, who became the star of the documentary “Spellbound” when she nailed “logorrhea” to win the 1999 Bee.

“Now it has brinkmanship, and things you wouldn’t see before - an 8-year-old spelling a German or polysyllabic word that I’ve never heard of,” said Lala, who will shortly start a medical residency at Brown University.

Beginning on Tuesday, more than 500 contestants from the United States and eight foreign countries take part in the 91st Scripps National Spelling Bee, to be held in Oxon Hill, Maryland, outside Washington. The championship finals are on Thursday night.

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Winnowed from 11 million hopefuls in schools around the world, contestants range in age from 8 to 15 and include the Bee’s first-ever twins - two sets of brothers from Utah and Mississippi.

Geoffrey Nunberg, a linguist at the University of California Berkeley, said the Bee was more of an intellectual exercise than a practical gauge of language skill since almost no one would ever use such recent Bee-winning words as “marocain,” “nunatak” and “guetapens.”

“It bears the same relationship to regular spelling as riding a BMX bike does to riding a bike in the street,” Nunberg said, referring to another extreme sport covered by ESPN.

Anamika Veeramani, who won the 2010 Bee by spelling “stromuhr,” called the contest “an American pastime” that had sharpened her language, even though nearly all of the words she had learned would never come up in everyday use.

“If you did everything just for the utility of it, I don’t think that we as human beings would do half of what we do,” said Veeramani, a Yale graduate who is headed for Harvard Medical School.

A STAGE AND A MICROPHONE

Sam Rega, who produced and directed the 2018 documentary “Breaking the Bee,” about Indian-Americans’ two-decade dominance of the Bee, said contestants were like high-performance athletes. Now only do they need to master the English language’s chaotic spelling system, they must back up the preparation with stamina and intense concentration.

“It’s just you on a stage, with a microphone and your knowledge base,” he said.

Spelling bees, which date back to 18th Century America, have enduring popularity as an all-American indicator of literacy and a reward system based on merit, Numberg said. As such, they have become a celebration of pride in communities, local schools and the complexities of the English language.

“We’re really proud of our persnickety spelling system,” he said, using a word that might challenge most Americans to spell correctly but probably not this year’s contestants.