In doing so, the 14-year-old emerged the top speller from a record-shattering 515 contestants at the national bee, compared with 291 last year, after organizers expanded eligibility.
Along the way, he had to outlast a field of 16 finalists who vanquished words such as "Praxitelean," "ispaghul" and "telyn" - sometimes without batting an eyelash - in a breathtaking show of spelling skill broadcast live on ESPN.
Nemmani also continued a longtime trend by becoming the 14th champion or co-champion of South Asian descent the bee has had in 11 consecutive years.
The 16 finalists took the stage at the Gaylord National Resort & Convention Center in Maryland to battle it out for the title of champion. The competition was, in a word, brutal. In the first round of ESPN-televised spelling Thursday night, nearly half of the finalists misspelled their words, including several crowd favorites such as Tara Singh, a 13-year-old from Kentucky who was competing at her fifth and final national bee.
The 16 finalists ranged in age from 11 to 14 and included nine girls and seven boys. The spellers came from all over the United States, plus one from Canada. And several had appeared at the national bee in previous years.
"I just try not to think about it," said Naysa Modi, a 12-year-old from Texas, competing in her fourth national bee, when asked about whether she might be a favorite to win this year. "That's too much pressure."
Thursday had begun with 41 spellers who qualified for the finals after surviving what was arguably the most intense competition in the bee's 93-year history.
This year more spellers qualified because of a new invitational program called "RSVBee," which allows those who didn't win a regional or state bee to still apply for the nationals if they had won their school bee or been a former national finalist.
The massive field of spellers began competing in earnest Tuesday by taking a written test so difficult that there were no perfect scores this year.
The expanded field also forced several logistical changes, such as an extra day of onstage spelling this week.
For hours on Tuesday and Wednesday, the spellers, who ranged in age from 8 to 14, tackled hundreds of mind-bending words, including "glossodynia" (a pain in the tongue), "stolon" (a horizontal branch from the base of a plant that produces new plants from buds at its tip or nodes) and "triturate" (to crush or grind).
The additional day of spelling meant that Jacques Bailly, the bee's longtime pronouncer - who is treated with almost iconic reverence by the spellers - took breaks for the first time to preserve his voice, handing over the microphone to associate pronouncer Brian Sietsema for a couple of the preliminary rounds.
It was hard for him to pull back, Bailly said Wednesday.
"I would probably run myself into the ground doing this, because I just love doing it," he said. "But I recognize with three days that I've got to do some pacing, to make sure I'm really on my game and we have full attention for every speller on there."
On Wednesday night, bee officials used test scores to determine that 41 spellers would move on to the finals, to compete under the glaring lights of prime-time television. (Bee rules state that no more than 50 contestants can advance to the finals.) The new wild-card program paid off for a number of spellers: Of the 41 finalists, 16 had qualified through RSVBee, and four of those contestants moved on to the prime-time finals.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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