Groutier. Zonular. Come again?

Those were two of the highly obscure words that helped Nigel Richards clinch the finals of the World Scrabble Championships in London on Sunday.

Even for a decorated Scrabble whiz, Mr. Richards, who is from New Zealand and lives in Malaysia, has a way with words.

Mr. Richards, 51, was the world Scrabble champion in 2007, 2011 and 2013. He also won the French edition of the championship in 2015 and again this year — apparently without actually speaking that language. (He is said to have memorized the French Scrabble dictionary.)

“He does have a reputation for being the best Scrabble player ever, and they know about him already,” Liz Fagerlund, a former president of the New Zealand Scrabble Association, told The New Zealand Herald in 2015, referring to Mr. Richards’s French opponents.