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

Definition of breakthrough

 (Entry 1 of 2)

1 warfare : an offensive military assault that penetrates and carries beyond a defensive line
2 : an act or instance of moving through or beyond an obstacle a breakthrough in the talks between the region's leaders a breakthrough agreement
3a : a sudden advance especially in knowledge or technique a medical breakthrough
b : a person's first notable success a breakthrough novel the actress's breakthrough performance

break through

broke through; broken through; breaking through; breaks through

Definition of break through (Entry 2 of 2)

intransitive verb

: to make a breakthrough

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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.
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Recent Examples on the Web: Noun Letersky offers less a historical breakthrough than finer brushstrokes on an American icon, whom the author describes as kind, courteous, formal, thoughtful, fearless, occasionally funny, a perfect gentleman and a devout patriot. Jeff Rowe, Star Tribune, 12 July 2021 But the true breakthrough came in December 2018, when authorities announced the rollout of a national 3G network, which would for the first time allow Cubans to access the internet from anywhere. Nicolás Rivero, Quartz, 12 July 2021 The breakthrough potentially set the stage for the most sweeping change in international taxation in a century. Kate Davidson, WSJ, 8 July 2021 This time, the breakthrough took just 19 minutes for the Rising (8-2-1), setting the course for an eventual 3-0 win. Theo Mackie, The Arizona Republic, 5 July 2021 Biden is attempting to simultaneously satisfy ardent Democrats and secure a bipartisan breakthrough, which requires serious legislative acrobatics. Eli Stokols, Los Angeles Times, 28 June 2021 Only a handful of females have raced regularly in the IndyCar series since Guthrie's breakthrough, most notably Danica Patrick. Paul Newberry, ajc, 7 May 2021 Impact occurs at the intersection of scientific breakthrough, entrepreneurial dynamism, and government support. Deena Shakir, Forbes, 11 Mar. 2021 In the rare instance of a breakthrough infection, as apparently was the case with the Phoenix Suns’ Chris Paul, the rest of the team can carry on. Mike Finger, San Antonio Express-News, 26 June 2021

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.

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First Known Use of breakthrough


1915, in the meaning defined at sense 1


1946, in the meaning defined above

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Time Traveler for breakthrough

Time Traveler

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

17 Jul 2021

Cite this Entry

“Breakthrough.” Dictionary, Merriam-Webster, Accessed 29 Jul. 2021.

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More Definitions for breakthrough



English Language Learners Definition of breakthrough

: a sudden increase in knowledge, understanding, etc. : an important discovery that happens after trying for a long time to understand or explain something
: a person's first important success


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

Kids Definition of breakthrough

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

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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