kryptonite

noun

kryp·​to·​nite ˈkrip-tə-ˌnīt How to pronounce kryptonite (audio)
variants or Kryptonite
in stories
: a substance that causes the comic-book character Superman to become weak when he is exposed to it

Note: In Superman stories, kryptonite in its most familiar form is a green mineral that originated as part of Superman's home planet of Krypton and that falls to Earth as a meteorite.

Superman tended to get more bummed out by Kryptonite than by anything going on in Clark Kent's life …Tom Russo
often used to describe something likened to kryptonite in causing someone's weakness, failure, etc.
In his career Thome has hit less than .240 against lefties. Lefthanded power pitching is Thome's KryptoniteJoe Posnanski
Ironic people always dissolve when confronted with earnestness, it's their kryptonite.Gillian Flynn
"Thin people know they need to either limit exposure to certain foods that trigger appetite or limit the quantity or frequency of those foods," says Gullo, whose personal kryptonite is pizza.Lorie Parch
Effortlessly good-looking, he was also a talented writer—that combo was my kryptonite.Taylor Orci

Examples of kryptonite in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
For all of his success at the sport’s highest level, Pittsburgh has somehow been Jackson’s kryptonite, pestering him into some of the worst performances of an otherwise Hall of Fame-worthy resume. Brian Wacker, Baltimore Sun, 14 Nov. 2024 Massive matchup at Roland Garros The only thing standing between Novak Djokovic and his first Olympic gold medal is … Carlos Alcaraz, arguably the Serbian’s biggest kryptonite nowadays. Torrey Hart, The Athletic, 4 Aug. 2024 Empowering Teams Through Autonomy and Accountability Micromanagement is the kryptonite of efficient leadership. Brent Gleeson, Forbes, 28 Nov. 2024 Griffins are thankful to have another season with Jonas Williams, but Loyola remains kryptonite. Steve Millar, Chicago Tribune, 24 Nov. 2024 See all Example Sentences for kryptonite 

Word History

Etymology

Krypton, Superman's home planet + -ite entry 1

First Known Use

1943, in the meaning defined above

Time Traveler
The first known use of kryptonite was in 1943

Dictionary Entries Near kryptonite

Cite this Entry

“Kryptonite.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/kryptonite. Accessed 22 Dec. 2024.

Last Updated: - Updated example sentences
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