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 Having already achieved Eastern Conference success with multiple victories this season over the Milwaukee Bucks, Toronto Raptors and Philadelphia 76ers, the Miami Heat got their breakthrough Tuesday night against the Boston Celtics. Ira Winderman,, "Robinson’s late 3s lift Butler-less Heat over Celtics 112-106," 4 Aug. 2020 And the race for a vaccine, though progressing rapidly, has yet to deliver a breakthrough. The Christian Science Monitor, "Fauci heads to Congress with a warning: Stay vigilant," 31 July 2020 And the race for a vaccine, though progressing rapidly, has yet to deliver a breakthrough. Matthew Perrone, Anchorage Daily News, "Fauci optimistic COVID-19 vaccine will be widely available, dismisses Trump tweet," 31 July 2020 Instead, White House aides seem to be growing more resigned to hoping for an outside event to change the trajectory of the contest, whether a serious misstep by Biden or, increasingly, a vaccine breakthrough. Zeke Miller, Star Tribune, "Trump seeks political shot in the arm in vaccine push," 27 July 2020 Instead of marking a scientific breakthrough, PlantWave stands an act of artistry that invites the users into a deeper conversation with the natural world. Elisia Guerena, Popular Mechanics, "The Plants That Make Music," 12 July 2020 But if soccer can pass this test and remain vigilant in the face of an uncured virus, that’s an important breakthrough for the broader sports world. Tim Sullivan, The Courier-Journal, "Louisville City FC fans take a solid step toward normalcy with debut of Lynn Family Stadium," 13 July 2020 French feminists, who have long sought to battle women’s oppression in a macho culture, welcomed the movement as a breakthrough that allowed victims to speak out at last — though no powerful French figures lost their jobs as a result. Arno Pedram,, "Women’s rights groups protest French ministers’ appointments," 7 July 2020 Global stocks are climbing on hopes of a vaccine breakthrough, and on a trickle of decent manufacturing and sales data, a further sign of a rebounding economy. Bernhard Warner, Fortune, "Global markets surge ahead of today’s big jobs report," 2 July 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

9 Aug 2020

Cite this Entry

“Breakthrough.” Dictionary, Merriam-Webster, Accessed 11 Aug. 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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