OXON HILL, Md. — Karthik Nemmani, of McKinney, Texas, outlasted 15 others in the finals Thursday night to win the 2018 Scripps National Spelling Bee.

Nemmani spelled the word “koinonia” correctly.

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 the eighth-grader 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 spellers took the stage Thursday night 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, 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.

To even get to that point, the finalists had to survive nearly five hours of onstage spelling that started Thursday morning. Bee officials said the plan had been to whittle down the field to about a dozen contestants for the prime-time competition. It would take five rounds of onstage spelling to get to 16, the largest group ever to head into the championship finals.

The 16 finalists ranged in age from 11 to 14 and include 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 Dallas competing in her fourth national bee, when asked after the Thursday afternoon spelling rounds about whether she might be a favorite to win.

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.

Of note, however: All five spellers who scored the highest on the test were among the 16 finalists. That included Modi, from Texas; Sravanth Malla, 14, of New York; Shruthika Padhy, 12, of New Jersey; and Aisha Randhawa, 12, of California; and eventual champion Nemmani.

Nemmani will receive $40,000 and a trophy, a $2,500 cash prize (and a complete reference library) from Merriam-Webster, trips to New York and Hollywood, and a pizza party for his school.