break·​through | \ ˈbrāk-ˌthrü How to pronounce breakthrough (audio) \
plural breakthroughs

Definition of breakthrough

 (Entry 1 of 2)

1a : a sudden advance especially in knowledge or technique a medical breakthrough
b : a person's first notable success often used before another noun a breakthrough novelthe actress's breakthrough performance
2a : an act or instance of moving through or beyond an obstacle a breakthrough in the talks between the region's leaders a breakthrough agreement
b : an instance of passing through a barrier or protection The ice under the surface begins to deteriorate, increasing the risk of breakthroughs.— Vicki Winger specifically, medical : infection occurring in someone who is fully vaccinated against an infectious agent A vaccine breakthrough occurs when a person tests positive for COVID-19 two weeks after being fully vaccinated against the disease … — David Rasbach often used before another noun Two other CDC studies of breakthrough cases at nursing homes showed the vaccines protected residents, even when the virus spread through the homes. — Maura Dolan … the academy recently recommended that children receive two doses of the chicken pox vaccine, rather than just one, because the additional dose bolsters immunity and may help reduce breakthrough infection. — Maria Raven
3 warfare : an offensive military assault that penetrates and carries beyond a defensive line

break through

broke through; broken through; breaking through; breaks through

Definition of break through (Entry 2 of 2)

intransitive verb

: to make a breakthrough

Synonyms & Antonyms for breakthrough

Synonyms: Noun

Antonyms: Noun

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Examples of breakthrough in a Sentence

Noun Researchers say they have made a major breakthrough in cancer treatment. The police have announced a breakthrough in the murder case. This job could be the breakthrough she's been waiting for.
Recent Examples on the Web: Noun The breakthrough follows the collaboration's 2019 release of the first image of a black hole, called M87(asterisk), at the center of the Messier 87 galaxy. Julia Musto, Fox News, 12 May 2022 Internationally beloved since the breakthrough of their second album Ágætis byrjun in 1999, Sigur Rós is back with the release of their first studio album since 2013. oregonlive, 10 May 2022 The Five, as colloquially called among hometown fans, never did get the big breakthrough the band had strived for. Brian Mccollum, Detroit Free Press, 5 May 2022 Cryptocurrencies could be the next great technological breakthrough. Washington Post, 29 Apr. 2022 The introduction of Ionic Originals debuts the first breakthrough in analog sound reproduction in more than 70 years, according to a release announcing the news. Fred Sahai, Billboard, 26 Apr. 2022 But the biggest breakthrough in theaters this April has been for family moviegoing. cleveland, 24 Apr. 2022 But the biggest breakthrough in theaters this April has been for family moviegoing. Jake Coyle, USA TODAY, 24 Apr. 2022 The breakthrough came in the 1974-75 season, when he was paired with left-winger Steve Shutt and scored 53 goals. David Shoalts, New York Times, 22 Apr. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'breakthrough.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of breakthrough


1915, in the meaning defined at sense 3


1946, in the meaning defined above

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Time Traveler for breakthrough

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The first known use of breakthrough was in 1915

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Dictionary Entries Near breakthrough

break the truce


break through

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Statistics for breakthrough

Last Updated

18 May 2022

Cite this Entry

“Breakthrough.” Dictionary, Merriam-Webster, Accessed 25 May. 2022.

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More Definitions for breakthrough


break·​through | \ ˈbrāk-ˌthrü How to pronounce breakthrough (audio) \

Kids Definition of breakthrough

: a sudden advance or successful development a breakthrough in medical research


break·​through | \ ˈbrāk-ˌthrü How to pronounce breakthrough (audio) \

Medical Definition of breakthrough

: infection occurring in someone who is fully vaccinated against an infectious agent often used before another noun breakthrough infections

More from Merriam-Webster on breakthrough

Nglish: Translation of breakthrough for Spanish Speakers

Britannica English: Translation of breakthrough for Arabic Speakers Encyclopedia article about breakthrough


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