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 Ron Dermer, Israel’s ambassador to America and one of Mr Netanyahu’s closest advisers, is said to have been behind the breakthrough. The Economist, "Next year in Jerusalem Serbia and Kosovo awkwardly embrace Israel," 12 Sep. 2020 The key breakthrough was in solid-state high-voltage switches that emerged in the early 2000s. Daniel Oberhaus, Wired, "Is Lightning-Fast Plasma the Key to a Cleaner Car Engine?," 9 Sep. 2020 The most prominent breakthrough involves proving a fundamental new law governing the tornado-like tubes of currents known as vortices. Quanta Magazine, "An Unexpected Twist Lights Up the Secrets of Turbulence," 3 Sep. 2020 But a breakthrough on state aid would be significant and inject impetus into the negotiations, one of the EU officials said. Ian Wishart,, "EU Presses U.K. to Reveal State-Aid Plans to Save Brexit Talks," 29 Aug. 2020 Aubameyang found the breakthrough in the 12th minute, latching onto Bukayo Saka's diagonal pass before curling into the net. Rob Harris, Star Tribune, "Community Shield: Aubameyang seals Arsenal win vs Liverpool," 29 Aug. 2020 The big breakthrough came when researchers in China made public the RNA sequence of the coronavirus, said Williamson, who spent 40 years as a professor at OSU. Special To The Oregonian/oregonlive, oregonlive, "Wastewater sampling proves useful in tracking coronavirus; coast program to expand to 43 Oregon cities," 28 Aug. 2020 But that will take time, and the likelihood that any single study will provide either a clear picture or a breakthrough is low. John Timmer, Ars Technica, "Dissecting the immune system’s response to COVID-19," 24 Aug. 2020 The breakthrough came in 1928, when competing American, French, and English research teams across Africa convened in Dakar to discuss the tragic case of one Adrian Stokes. Joshua Sokol, The Atlantic, "The Worst Animal in the World," 20 Aug. 2020

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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Statistics for breakthrough

Last Updated

14 Sep 2020

Cite this Entry

“Breakthrough.” Dictionary, Merriam-Webster, Accessed 20 Sep. 2020.

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More Definitions for breakthrough


How to pronounce break through (audio)

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

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